Invading black holes cause ‘cosmic flashes’

Washington, September 19 (ANI): Mathematicians at the University of Leeds, UK, have determined that cosmic flashes, known as gamma ray bursts, are produced by jets of plasma that originate from invading black holes.

Gamma ray bursts are beams of high-energy radiation that are similar to the radiation emitted by explosions of nuclear weapons.

The orthodox model for this cosmic jet engine involves plasma being heated by neutrinos in a disk of matter that forms around a black hole, which is created when a star collapses.

But, mathematicians at the University of Leeds, have come up with a different explanation: the jets come directly from black holes, which can dive into nearby massive stars and devour them.

Their theory is based on recent observations by the Swift satellite, which indicates that the central jet engine operates for up to 10,000 seconds – much longer than the neutrino model can explain.

Mathematicians believe that this is evidence for an electromagnetic origin of the jets, that is, that the jets come directly from a rotating black hole, and that it is the magnetic stresses caused by the rotation that focus and accelerate the jet’s flow.

For the mechanism to operate, the collapsing star has to be rotating extremely rapidly.

This increases the duration of the star’s collapse as the gravity is opposed by strong centrifugal forces.

One particularly peculiar way of creating the right conditions involves not a collapsing star, but a star invaded by its black hole companion in a binary system.

The black hole acts like a parasite, diving into the normal star, spinning it with gravitational forces on its way to the star’s centre, and finally eating it from the inside.

“The neutrino model cannot explain very long gamma ray bursts and the Swift observations, as the rate at which the black hole swallows the star becomes rather low quite quickly, rendering the neutrino mechanism inefficient, but the magnetic mechanism can,” said Professor Komissarov from the School of Mathematics at the University of Leeds.

“Our knowledge of the amount of the matter that collects around the black hole and the rotation speed of the star allow us to calculate how long these long flashes will be – and the results correlate very well with observations from satellites,” he added. (ANI)

Stephen William Hawking | President Obama Honored | Presidential Medal of Freedom | Nation’s Highest Civilian Honor | British Theoretical Physicist

Stephen William Hawking | President Obama Honored | Presidential Medal of Freedom | Nation’s Highest Civilian Honor | British Theoretical Physicist

Stephen William Hawking, CH, CBE, FRS, FRSA ,born on 8th January 1942, is a British theoretical physicist. Hawking is the Lucasian Professor of Mathematics at the University of Cambridge (but intends to retire from this post in 2009), a Fellow of Gonville and Caius College, Cambridge and the distinguished research chair at Waterloo’s Perimeter Institute for Theoretical Physics.

He is known for his contributions to the fields of cosmology and quantum gravity, especially in the context of black holes. He has achieved most of his success with works of popular science in which he discusses his own theories and cosmology in general; these include the runaway best seller A Brief History of Time, which stayed on the British Sunday Times bestsellers list for a record-breaking 237 weeks.

Hawking has a neuro muscular dystrophy that is related to amyotrophic lateral sclerosis (ALS), a condition that has progressed over the years and has left him almost completely paralysed.

Hawking’s key scientific works to date have included providing, with Roger Penrose, theorems regarding singularities in the framework of general relativity, and the theoretical prediction that black holes should emit radiation, which is today known as Hawking radiation (or sometimes as Bekenstein-Hawking radiation).

He is a world-renowned theoretical physicist whose scientific career spans over 40 years. His books and public appearances have made him an academic celebrity. He is an Honorary Fellow of the Royal Society of Arts, and a lifetime member of the Pontifical Academy of Science.

On August 12, 2009, President Obama honored on Wednesday with the Presidential Medal of Freedom, the nation’s highest civilian honor to Stephen William Hawking.

Astronomers see high-speed galaxy collision in action

Washington, July 10 (ANI): Astronomers at the Chandra X-ray Observatory have spotted a galaxy collision in action, with one galaxy passing through the core of other galaxies at almost 2 million miles per hour.

The image obtained is of Stephan’s Quintet, a compact group of galaxies discovered about 130 years ago and located about 280 million light years from Earth.

Four of the galaxies in the group are visible in the optical image from the Canada-France-Hawaii Telescope.

A labeled version identifies these galaxies (NGC 7317, NGC 7318a, NGC 7318b and NGC 7319) as well as a prominent foreground galaxy (NGC 7320) that is not a member of the group.

The galaxy NGC 7318b is passing through the core of galaxies at almost 2 million miles per hour, and is thought to be causing the ridge of X-ray emission by generating a shock wave that heats the gas.

Additional heating by supernova explosions and stellar winds has also probably taken place in Stephan’s Quintet.

A larger halo of X-ray emission, detected by ESA’s (European Space Agency’s) XMM-Newton could be evidence of shock heating by previous collisions between galaxies in this group.

Some of the X-ray emissions are likely caused by binary systems containing massive stars that are losing material to neutron stars or black holes.

Stephan’s Quintet provides a rare opportunity to observe a galaxy group in the process of evolving from an X-ray faint system dominated by spiral galaxies to a more developed system dominated by elliptical galaxies and bright X-ray emission.

According to scientists, being able to witness the dramatic effect of collisions in causing this evolution is important for increasing the understanding of the origins of the hot, X-ray bright halos of gas in groups of galaxies.

Stephan’s Quintet shows an additional sign of complex interactions in the past, notably the long tails visible in the optical image.

These features were probably caused by one or more passages through the galaxy group by NGC 7317. (ANI)

Origin of very high-energy gamma rays pinpointed to giant black hole

Washington, July 3 (ANI): Using a worldwide combination of diverse telescopes, astronomers have discovered that a giant galaxy’s bursts of very high energy gamma rays are coming from a region very close to the supermassive black hole at its core.

The discovery provides important new information about the mysterious workings of the powerful “engines” in the centers of innumerable galaxies throughout the Universe.

The galaxy M87, 50 million light-years from Earth, harbors at its center a black hole more than six billion times more massive than the Sun.

Black holes are concentrations of matter so dense that not even light can escape their gravitational pull.

The black hole is believed to draw material from its surroundings – material that, as it falls toward the black hole, forms a tightly-rotating disk.

Processes near this “accretion disk,” powered by the immense gravitational energy of the black hole, propel energetic material outward for thousands of light-years.

This produces the “jets” seen emerging from many galaxies. In 1998, astronomers found that M87 also was emitting flares of gamma rays a trillion times more energetic than visible light.

However, the telescopes that discovered these bursts of very high-energy gamma rays could not determine exactly where in the galaxy they originated.

In 2007 and 2008, the astronomers using these gamma-ray telescopes combined forces with a team using the National Science Foundation’s continent-wide Very Long Baseline Array (VLBA), a radio telescope with extremely high resolving power, or ability to see fine detail.

“Combining the gamma-ray observations with the supersharp radio ‘vision’ of the VLBA allowed us to see that the gamma rays are coming from a region very near the black hole itself,” said Craig Walker, of the National Radio Astronomy Observatory (NRAO).

“Pinning down this location addresses what was an open question and provides important clues for understanding how such highly energetic emissions are produced in the jets of active galaxies,” said Matthias Beilicke, of Washington University in St. Louis.

The radio flare began at about the time of the gamma-ray flares, but continued to increase in brightness for at least two months.

“This tells us that energetic material burst out very close to the black hole, causing the gamma rays to be emitted and the radio flare to begin. As that material traveled down the jet, expanding and losing energy, the gamma-ray emission ceased, but the radio continued to increase in brightness,” Walker explained.

“The VLBA showed us with great precision where the radio emission came from, so we know the gamma rays came from closer in toward the black hole,” he added. (ANI)

Milky Way survived ancient heat wave because of dark matter

Washington, July 1 (ANI): A new theory by scientists says that our Milky Way galaxy survived intense heat generated by the “ignition” of the Universe about half-a-billion years after the Big Bang, because it was already immersed in a large clump of dark matter that trapped gases inside it.

Tiny galaxies, inside small clumps of dark matter, were blasted away by the heat that reached approximate temperatures of between 20,000 and 100,000 degrees centigrade, according to the scientists, including experts at Japan’s University of Tsukuba.

The researchers said that the early Milky Way, which had begun forming stars, held on to the raw gaseous material from which further stars would be made.

This material would otherwise have been evaporated by the high temperatures generated by the “ignition”.

Using computer simulations carried out by the international Virgo Consortium (which is led by Durham), the scientists examined why galaxies like the Milky Way have so few companion galaxies or satellites.

Astronomers have found a few dozen small satellites around the Milky Way, but the simulations revealed that hundreds of thousands of small clumps of dark matter should be orbiting our galaxy.

Dark matter is thought to make up 85 per cent of the Universe’s mass and is believed to be one of the building blocks of galaxy formation.

The scientists said the heat from the early stars and black holes rendered this dark matter barren and unable to support the development of satellite star systems.

According to Joint lead investigator Professor Carlos Frenk, Director of the Institute for Computational Cosmology, at Durham University, “The validity of the standard model of our Universe hinges on finding a satisfactory explanation for why galaxies like the Milky Way have so few companions.”

“The simulations show that hundreds of thousands of small dark matter clumps should be orbiting the Milky Way, but they didn’t form galaxies,” he explained.

“We can demonstrate that it was almost impossible for these potential galaxies to survive the extreme heat generated by the first stars and black holes,” he added.

“The heat evaporated gas from the small dark matter clumps, rendering them barren. Only a few dozen front-runners which had a head start on making stars before the Universe ignited managed to survive,” he further added.

By providing a natural explanation for the origin of galaxies, the simulations support the view that cold dark matter is the best candidate for the mysterious material believed to make up the majority of our Universe. (ANI)

Cosmic “ghost” found lurking around supermassive black hole

Washington, May 29 (ANI): NASA’s Chandra X-ray Observatory has found a cosmic “ghost” lurking around a distant supermassive black hole, which is the first detection of such a high-energy apparition, and may be evidence of a huge eruption produced by the black hole.

The X-ray ghost, so-called because a diffuse X-ray source has remained after other radiation from the outburst has died away, is in the Chandra Deep Field-North, one of the deepest X-ray images ever taken.

The source, a.k.a. HDF 130, is over 10 billion light-years away and existed at a time 3 billion years after the Big Bang, when galaxies and black holes were forming at a high rate.

“We’d seen this fuzzy object a few years ago, but didn’t realize until now that we were seeing a ghost”, said Andy Fabian of the Cambridge University in the United Kingdom.

“It’s not out there to haunt us, rather it’s telling us something – in this case what was happening in this galaxy billions of year ago,” he added.

Fabian and colleagues think the X-ray glow from HDF 130 is evidence for a powerful outburst from its central black hole in the form of jets of energetic particles traveling at almost the speed of light.

When the eruption was ongoing, it produced prodigious amounts of radio and X-radiation, but after several million years, the radio signal faded from view as the electrons radiated away their energy.

However, less energetic electrons can still produce X-rays by interacting with the pervasive sea of photons remaining from the Big Bang – the cosmic background radiation.

Collisions between these electrons and the background photons can impart enough energy to the photons to boost them into the X-ray energy band.

This process produces an extended X-ray source that lasts for another 30 million years or so.

“This ghost tells us about the black hole’s eruption long after it has died,” said co-author Scott Chapman, also of Cambridge University. “This means we don’t have to catch the black holes in the act to witness the big impact they have,” he added.

This is the first X-ray ghost ever seen after the demise of radio-bright jets.

In HDF 130, only a point source is detected in radio images, coinciding with the massive elliptical galaxy seen in its optical image.

This radio source indicates the presence of a growing supermassive black hole.

“This result hints that the X-ray sky should be littered with such ghosts, especially if black hole eruptions are as common as we think they are in the early Universe,” said co-author Caitlin Casey, also of Cambridge. (ANI)

CORRECTED – Astronauts tackle last items on Hubble fix-up list

Shuttle Atlantis astronauts returned to the Hubble Space Telescope on Monday for a final spacewalk to install fresh batteries, thermal shields and a sensor to pinpoint celestial targets for research.

Lead spacewalker John Grunsfeld and partner Andrew Feustel left the shuttle’s air lock at about 8:30 a.m. EDT (1230 GMT), almost an hour ahead of schedule.

“OK, Drew. Let’s go and be productive,” Grunsfeld said as they headed out toward Hubble.

Their primary job is to replace three of Hubble’s batteries and one of its star-tracking sensors, which are used to aim the observatory at celestial targets.

The astronauts also hope to make up some work left over from Sunday’s spacewalk by crew mates Michael Massimino and Michael Good, who battled stuck bolts and equipment glitches in their attempt to revive one of Hubble’s dead science instruments.

The Space Telescope Imaging Spectrograph, known as STIS, was used to hunt for black holes and probe the gas and dust between galaxies before a power failure shut it down in 2004.

Tests of the instrument showed the repair was successful, NASA spokesman Rob Navias said.

Grunsfeld and Feustel plan to replace the rest of Hubble’s batteries. Three of the six batteries were replaced on Thursday during the mission’s first spacewalk.

Swapping the remaining three will complete NASA’s primary goals for the mission, the fifth and final servicing call to Hubble before the shuttle fleet is due to be retired next year.

FRIDAY RETURN PLANNED

The Atlantis crew plans to release Hubble back into orbit on Tuesday and return to the Kennedy Space Center in Florida on Friday.

During four previous spacewalks, astronauts installed a new camera and light-splitting spectrograph, replaced Hubble’s positioning system, repaired two instruments and attached a docking ring so a robotic spacecraft can be sent to remove Hubble from orbit at the end of its operational lifetime.

The upgrades are expected to keep Hubble on the cutting edge of scientific exploration for at least five years so it can work in tandem with its replacement, the James Webb Space Telescope.

Grunsfeld and Feustel also hope to have enough time to install metal shields over the telescope’s instrument bays to help protect the observatory from the harsh environment of space. One of the shields was scheduled to be attached on Sunday, but the astronauts ran out of time.

NASA designed covers for three areas of the telescope and hopes to get to at least two of them on Monday.

Astronauts begin 3rd spacewalk for Hubble upgrades

Astronauts begin 3rd spacewalk for Hubble upgrades Washington – Astronauts John Grunsfeld and Andrew Feustel began Saturday the current shuttle mission’s third spacewalk to upgrade the Hubble Space Telescope, the US space agency NASA said.

The agency’s website said that the third of the scheduled five spacewalks on the STS-125 mission began at 9:35 am EDT (1335 GMT).

Grunsfeld and Feustel will install a new instrument known as the Cosmic Origins Spectrograph, a device designed to break up light into its components.

It will allow astronomers to study the large-scale structure and origins of the universe, including how galaxies, stars and planets form and how elements developed.

In two spacewalks so far, astronauts have installed a new camera on the ageing telescope, and replaced a computer and the gyroscopes that keep it aligned.

Scientists say the upgrades, which US space agency NASA hopes will extend Hubble’s life span until at least 2014, will continue to provide clues about the origin and nature of the universe.

Since its launch in 1990, Hubble has helped scientists to place the age of the universe at 13.7 billion years, learn that black holes are at the centre of most galaxies, monitor planetary formation and discover that the universe is expanding at an ever-faster pace. (dpa)

Star crust found to be 10 billion times stronger than steel

Washington, May 7 (ANI): A new research by a scientist has shown that the crusts of neutron stars are 10 billion times stronger than steel or any other of the earth’s strongest metal alloys.

The research was done by Charles Horowitz, a professor in the IU (Indiana University) College of Arts and Sciences’ Department of Physics.

He came to came to the conclusion after large-scale molecular dynamics computer simulations were conducted at Indiana University and Los Alamos National Laboratory in New Mexico.

Exhibiting extreme gravity while rotating as fast as 700 times per second, neutron stars are massive stars that collapsed once their cores ceased nuclear fusion and energy production.

The only things more dense are black holes, as a teaspoonful of neutron star matter would weigh about 100 million tons.

Scientists want to understand the structure of neutron stars, in part, because surface irregularities, or mountains, in the crust could radiate gravitational waves and in turn may create ripples in space-time.

“We modeled a small region of the neutron star crust by following the individual motions of up to 12 million particles,” Horowitz said of the work conducted through IU’s Nuclear Theory Center in the Office of the Vice Provost for Research.

“We then calculated how the crust deforms and eventually breaks under the extreme weight of a neutron star mountain,” he added.

Performed on a large computer cluster at Los Alamos National Laboratory and built upon smaller versions created on special-purpose molecular dynamics computer hardware at IU, the simulations identified a neutron star crust that far exceeded the strength of any material known on earth.

The crust could be so strong as to be able to elicit gravitational waves that could not only limit the spin periods of some stars, but that could also be detected by high-resolution telescopes called interferometers, the modeling found.

“The maximum possible size of these mountains depends on the breaking strain of the neutron star crust,” Horowitz said.

“The large breaking strain that we find should support mountains on rapidly rotating neutron stars large enough to efficiently radiate gravitational waves,” he added.

Because of the intense pressure found on neutron stars, structural flaws and impurities that weaken things like rocks and steel are less likely to strain the crystals that form during the nucleosynthesis that occurs to form neutron star crust.

Squeezed together by gravitational force, the crust can withstand a breaking strain 10 billion times the pressure it would take to snap steel. (ANI)

Astronomers spot most distant object in the Universe

London, April 28 (ANI): Astronomers have spotted the most distant object yet confirmed in the universe, which is a self-destructing star that exploded 13.1 billion light years from Earth.

According to a report in New Scientist, it detonated just 640 million years after the big bang, around the end of the cosmic “dark ages”, when the first stars and galaxies were lighting up space.

The object is a gamma-ray burst (GRB) – the brightest type of stellar explosion.

GRBs occur when massive, spinning stars collapse to form black holes and spew out jets of gas at nearly the speed of light.

These jets send gamma rays our way, along with “afterglows” at other wavelengths, which are produced when the jet heats up surrounding gas.

The burst, dubbed GRB 090423 for the date of its discovery on April 23, was originally spotted by NASA’s Swift satellite at 0755 GMT.

Within an hour, astronomers began training ground-based telescopes on the same patch of sky to study the burst’s infrared afterglow.

Some of the first observations were made on Mauna Kea in Hawaii with the United Kingdom Infrared Telescope and the Gemini North telescope.

Other telescopes later measured the spectrum of the afterglow, revealing that the burst detonated about 13.1 billion light years from Earth.

“It’s the most distance gamma-ray burst, but it’s also the most distant object in the universe overall,” said Edo Berger of the Harvard-Smithsonian Center for Astrophysics, a member of the team that observed the afterglow with Gemini North.

This burst lies at a redshift of 8.2, more distant than the previous GRB record holder, which lay at a redshift of 6.7.

Other astronomers have claimed to find galaxies at even greater distances – at redshifts of 10 and 9, but those findings are still ambiguous, according to Joshua Bloom of the University of California, Berkeley, who observed the afterglow using the Gemini South telescope in Chile.

Until now, the record holder for the farthest galaxy had a spectroscopically confirmed redshift of 6.96.

The burst’s immense distance makes the now-dead star the earliest object to be discovered from an era called ‘reionisation’, which occurred within the first billion years after the big bang.

At that time, an obscuring fog of neutral hydrogen atoms was being burned off by radiation from the first stars and galaxies, and possibly also from the annihilation of dark matter particles.

“For astronomy, this is a watershed event,” Bloom told New Scientist. “This is the beginning of the study of the universe as it was before most of the structure that we know about today came into being,” he added. (ANI)

Easter tourism a barometer for Croatian economy, government

Zagreb – In the midsts of the global economic meltdown, tourism-dependent Croatia is anxiously awaiting the first results of the Easter holiday break. With holiday-makers to the former Yugoslav republic providing nearly a quarter of the country’s GDP, tourism figures aren’t just of interest to the hotel and catering trade – they could well affect the prospects for the government in Zagreb.

Even though first signs show high visitor numbers and packed hotels, any relief is tempered by the knowledge that the year ahead will still be tricky.

Official statistics are not available yet, but it is clear that the numbers of holiday-makers exceeded some of the bleaker forecasts from experts – including the government’s own Tourism Minister, Damir Bajs.

Bajs predicted a 3 per cent decline in visitor numbers for 2009. Others went further, with the head of the national hotel owners organisation, Franko Palma, predicting a double-digit drop.

Despite the good showing over the Easter weekend, he cautions against too much optimism.

“Last year Easter fell earlier in the season and the weather was nasty, so it isn’t clever to jump to a conclusion that growth for Easter this year is a real signal,” Palma said.

Palma said the crunch periods were the so-called black holes of May, and late August to early September.

There is much riding on it. Indeed, the success or failure of the tourist season may actually be the hottest political question in the country.

Tourism is Croatia’s biggest income-earner and a bad season could force Prime Minister Ivo Sanader’s cabinet into a second emergency budget in the autumn and to request credit from the International Monetary Fund – both of which would be unpopular measures.

With around 9.5 billion dollars last year, tourism generated 22 per cent of the Croatian gross domestic product (GDP), more than any other sector of the economy.

In its best ever year, 2008, around 10.6 million tourists came to Croatia, mostly staying along its beautiful, 1,100-kilometre Adriatic coast.

One in five of all tourists were from Germany, with Austria and Slovenia close behind, with in total 54.6 million nights being spent in Croatia by tourists.

Croatia’s tourism sector has grown and gone up market to match the influx, with seven 5-star hotels and 67 4-star hotels springing up in the past two years alone.

After a long boom, predictions of 3 to 11 percent drops in revenue have created waves of panic in the industry.

The government responded with a series of measures to boost tourism, not least a 14.5 million dollar advertising campaign in strategic markets.

It even advertised in its former Yugoslav sister republics, Serbia and Bosnia, with whom relations are prickly.

Another part of the government’s emergency action plan was to scrap entry visas for visitors from the emerging markets of Russian and Ukraine, scrapping entry charges for some museums, and employing famous athletes and celebrities to promote Croatia as “tourism ambassadors.”

In a sign of the straightened times, old Russian jet aircraft, long-since banned from Croatian airports because they are too noisy for EU – which Croatia is due to join – will again be landing this summer, as they bring in spending guests.

Despite all this, the real fortunes of the critical Croatian tourism industry will only be known at the end of the season.

“It started well, but the finish is more important,” a columnist with the internet portal Net concluded. (dpa)

British business – April 13

FSA PREPARES FILE ON CATTLES AMID CONCERN OVER BLACK HOLE

The Financial Services Authority is preparing a file on Cattles(CTT.L), as shareholders become increasingly concerned as to how the company’s 700 million pound black hole in its loan provisioning was kept secret from them for more than two years.

Cattles blamed a “breakdown in internal controls” on the long-running risk-mismanagement scandal and suspended six executives as a result.

Directors at the subprime lender are believed to be in close contact with the FSA and have passed on Deloitte’s draft report which provides some details on where the black holes occurred.

BT FACES MULTIMILLION HIT ON NHS COMPUTERS

BT Group’s (BT.L) struggling Global Services Division is expected to become the third major contractor in as many years to take a multimillion pound writedown on its work with the NHS’ computer system. The writedown, to be announced next month, is likely to be coupled with news of thousands of job losses in a drive to cut costs.

There are also fears that BT could be forced to double its pension scheme contributions to between 500 million to one billion pounds, placing the group’s final dividend in doubt.

Accenture and Fujitsu have already quit similar contracts with the National Programme for IT, writing off hundreds of millions of pounds in the process.

Prepared For Reuters by Durrants

The Times

BARCLAYS FUND MANAGERS SET TO WIN HIGHER CASH PAYOUTS.

Hundreds of fund managers at Barclays (BARC.L) will scoop multimillion-pound windfalls if the sale of Barclays Global Investors is completed.

CVC Capital Partners agreed last week on a 2.8 billion pound deal to purchase iShares, which accounts for a fifth of BGI’s assets under management. These assets total one trillion pounds. Barclays is examining the sale of the whole of BGI as part of a contractual ‘go shop’ agreement with CVC.

Completion of a BGI sale would mean that about 200 BGI staff, who hold equity in the assets manager, will share a total payout of about 90 million pounds in cash.

ONLINE PRICE WAR LOOMS AS WAITROSE ENDS DELIVERY CHARGE

As Waitrose announces it is scrapping delivery costs for online purchases, pressure is mounting on big grocery chains such as Tesco (TSCO.L) and J Sainsbury (SBRY.L) to follow suit. A price war in online food shopping will place greater pressure on margins, which could prompt grocers to seek further price cuts from suppliers.

Waitrose said that it would waive delivery charges for purchases in excess of 50 pounds, beginning on Wednesday. At present, delivery charges vary and can cost up to seven pounds a time. The move would be costly for Waitrose’s rivals to follow but would cut customer’s bills for internet purchases by between five and ten per cent.

UNION FURY AS VIRGIN MEDIA PLANS BONUSES AFTER JOBS CULL

A few months after laying off 2,200 employees, Virgin Media has announced plans to award executives bonuses equivalent to up to 100 per cent of their basic salary.

Trade unions expressed their displeasure at this drastically different treatment of employees and management. “At a time when people are losing their jobs and there’s a lot of uncertainty, the executives should be taking a lead and looking to forgo these bonuses,” said Grace Mitchell of the Communication Workers Union. T

he company stressed that only staff who had hit performance targets would be considered for bonuses.

Daily Telegraph

BANKS THREATEN TO WITHDRAW SUPPORT FOR TIGER TIGER

Novus Leisure, the firm that operates the bar chain Tiger Tiger, wrote to landlords last week asking for rent cuts, with Novus’ lenders RBS (RBS.L) and Barclays (BARC.L) threatening to put Tiger Tiger into administration if it is not made more cost efficient.

Accountancy and restructuring firm Grant Thornton has been brought in to assist with negotiations between Novus and its landlords, which include Land Securities and Prudential (PRU.L). An offer by Novus’ private equity owners Cognetas to invest 15 million pounds into Novus was rejected by RBS and Barclays in March.

DEBT FOR EQUITY SWAP FOR FOXTONS

A row is brewing between Foxtons, its owner and its lenders over a rumoured debt-for-equity swap. Reports suggest BC Partners,

Foxtons’ private equity owners, are in talks with Bank of America and Mizuho to write off between 60 and 90 million pounds in return for taking a large stake in the business, with BC Partners injecting a further 50 million pounds into the estate agent.

Sources close to the lenders have confirmed the negotiations, but people close to BC Partners have dismissed all claims. Foxtons was bought by BC Partners in 2007 for 370 million pounds.

HSBC PUTS LONDON HQ BACK ON MARKET

HSBC’s (HSBA.L) Canary Wharf headquarters have been put back on the market, just months after it re-acquired the property from Metrovacesa (MVC.MC). HSBC sold the tower in 2007 in a sale and leaseback deal, but bought it back in December making a profit of between 250 and 300 million pounds.

Sources claim HSBC is once again looking to sell the building as part of a global series of property sell-offs which it hopes will raise around 2.5 billion pounds. It is unclear why HSBC is selling several prized properties at a time when the commercial property market is falling.

The Independent

BT POISED TO CUT 10,000 MORE JOBS AND SLASH FINAL DIVIDEND

BT (BT.L) is to announce a further 10,000 jobs cuts, writedowns of about 1.5 billion pounds and a 60 per cent cut in its dividend, as it tries to turnaround the Global Services division.

The redundancies will be spread across the global workforce and follow the 10,000 jobs it has already culled over the past year. Global Services, which provides IT and telecoms services to multinational companies and government bodies, suffered a 501 million pound loss for the third quarter to December 31. The firm will also likely be hit by contribution to address an eight billion pound pension fund deficit.

JJB SEEKS TO IDENTIFY WHO BOUGHT TEN PER CENT STAKE

JJB Sports (JJB.L) is to send out 793 legal notices to investors, as it tries to unearth who bought a ten per cent stake in the troubled sports retailer, which was then sold off two weeks ago.

While the FSA is looking into the purchases, no party has yet been confirmed or found. It comes at a critical time for JJB, which is trying to safeguard its future through a company voluntary arrangement.

On 31 March, administrators at collapsed Kaupthing Bank sold off a 23 per cent stake in JJB. Monecor had bought a 13 per cent stake, and 10 per cent still remains unaccounted for.

STANDARD CHARTERED BANKER POCKETS 16 MILLION POUNDS

Singapore based Karam Butalia received a 16 million pound pay packet after leaving Standard Chartered (STAN.L) early last year.

The pay deal for Butalia makes him Britain’s best-paid employee at any British bank, and comes from a string of private equity deals he engineered over his six years at the bank. The bank’s former global head of private equity received a package four times larger than that received by Peter Sands, Standard Chartered’s chief executive.

The revelations about the award, comes at a time where banking bonuses have come under intense public scrutiny.

The Guardian

CITY WATCHDOG TO INVESTIGATE TOP BANKERS’ FAILURES AT RBS.

The Financial Services Authority is to investigate the conduct of Royal Bank of Scotland’s (RBS.L) and HBOS’ HBOS.L executives in the days leading up to the banks’ state rescues.

The ‘big four’ accountancy firms – KPMG, Deloitte, PricewaterhouseCoopers and Ernst and Young – are believed to have been invited to bid for work relating to the investigation, which is expected to launch within weeks.

The government needed to inject 20 million pounds to save RBS and waive competition rules to allow LloydsTSB (LLOY.L) to rescue HBOS. The FSA is not expecting to uncover criminal wrongdoing, but will examine whether shareholders received enough information.

Black holes that can regulate the rate at which they grow

Washington, March 26 (ANI): New results from NASA’s Chandra X-ray Observatory have suggested that a special class of black holes have a mechanism for regulating the rate at which they grow, and can shut off the high-speed jets they produce.

Some stellar-mass black holes launch powerful jets of particles and radiation, like seen in quasars, and are called “micro-quasars”.

The new study looks at a famous micro-quasar in our own Galaxy, and regions close to its event horizon, or point of no return.

This system, GRS 1915+105 (GRS 1915 for short), contains a black hole about 14 times the mass of the Sun that is feeding off material from a nearby companion star.

As the material swirls toward the black hole, an accretion disk forms.

This system shows remarkably unpredictable and complicated variability ranging from timescales of seconds to months, including 14 different patterns of variation.

These variations are caused by a poorly understood connection between the disk and the radio jet seen in GRS 1915.

Chandra, with its spectrograph, has observed GRS 1915 eleven times since its launch in 1999.

These studies reveal that the jet in GRS 1915 may be periodically choked off when a hot wind, seen in X-rays, is driven off the accretion disk around the black hole.

The wind is believed to shut down the jet by depriving it of matter that would have otherwise fueled it. Conversely, once the wind dies down, the jet can re-emerge.

“We think the jet and wind around this black hole are in a sort of tug of war,” said Joseph Neilsen, Harvard graduate student and lead author of the research paper. “Sometimes one is winning and then, for reasons we don’t entirely understand, the other one gets the upper hand,” he added.

The latest Chandra results also show that the wind and the jet carry about the same amount of matter away from the black hole.

This is evidence that the black hole is somehow regulating its accretion rate, which may be related to the toggling between mass expulsion via either a jet or a wind from the accretion disk.

Self-regulation is a common topic when discussing supermassive black holes, but this is the first clear evidence for it in stellar-mass black holes.

According to Julia Lee, assistant professor in the Astronomy department at the Harvard-Smithsonian Center for Astrophysics, “It is exciting that we may be on the track of explaining two mysteries at the same time: how black hole jets can be shut down and also how black holes regulate their growth.” By Sarda Lahangir (ANI)

Scientists observe the largest exploding star yet seen

Washington, March 24 (ANI): Scientists at the Weizmann Institute of Science and San Diego State University have observed the largest exploding star yet seen, which is the size of 50 suns.

While exploding stars, called supernovae, have been viewed with everything from the naked eye to high-tech research satellites, no one had directly observed what happens when a really huge star blows up.

Dr. Avishay Gal-Yam of the Weizmann Institute’s Faculty of Physics and Professor Douglas Leonard of San Diego State University recently located and calculated the mass of a gigantic star on the verge of exploding, following through with observations of the blast and its aftermath.

As they continued to track the spectacular event, they found that most of the star’s mass collapsed in on itself, resulting in a large black hole.

Their findings have lent support to the reigning theory that stars ranging from tens to hundreds of times the mass of our sun all end up as black holes.

Until now, none of the supernovae stars that scientists had managed to measure had exceeded a mass of 20 suns.

Gal-Yam and Leonard were looking at a specific region in space using the Keck Telescope on Mauna Kea in Hawaii and the Hubble Space Telescope.

Identifying the about-to-explode star, they calculated its mass to be equal to 50-100 suns. Continued observation revealed that only a small part of the star’s mass was flung off in the explosion.

According to Gal-Yam, most of the material was drawn into the collapsing core as its gravitational pull mounted.

In subsequent telescope images of that section of the sky, the star seems to have disappeared. In other words, the star has now become a black hole – so dense that light can’t escape. (ANI)

Astronomers discover a pair of twin black holes

Washington, March 5 (ANI): Astronomers from the National Optical Astronomy Observatory (NOAO) in Tucson, Arizona, have found what looks like a pair of twin black holes, orbiting each other in the center of one galaxy.

It has been postulated that twin black holes might exist, but it took an innovative, systematic search to find such a rare pair.

The newly identified black holes appear to be separated by only 1/10 of a parsec (1/3 of a light-year) – a tenth of the distance from Earth to the nearest star (other than the Sun).

This discovery of the most plausible binary black hole candidate ever found may lead to a greater understanding of how massive black holes form and evolve at the centers of galaxies.

After a galaxy forms it is likely that a massive black hole can also form at its center. Since many galaxies are found in clusters of galaxies, individual galaxies can collide with each other as they orbit in the cluster.

The mystery is what happens to these central black holes when galaxies collide and ultimately merge together.

Theory predicts that they will orbit each other and eventually merge into an even larger black hole.

The signature of a black hole in a galaxy has been known for many years. The material falling into a black hole emits light in narrow wavelength regions forming emission lines which can be seen when the light is dispersed into a spectrum.

These emission lines carry the information about the speed and direction of the black hole and the material falling into it.

If two black holes are present, they would orbit each other before merging and would have a characteristic dual signature in their emission lines.

This signature has now been found.

Former NOAO Director Todd Boroson and NOAO Astronomer Tod Lauer used data from the Sloan Digital Sky Survey, made with a 2.5-meter diameter telescope at Apache Point in southern New Mexico, to look for this characteristic dual black hole signature among 17,500 quasars discovered by the survey.

Boroson and Lauer had to especially careful to eliminate the possibility that they were seeing two galaxies, each with its own black hole, superimposed on each other.

To try to eliminate this superposition possibility, they determined that the quasars were at the same redshift-determined distance and that there was a signature of only one host galaxy.

The smaller black hole has a mass 20 million times that of the Sun; the larger one is 50 times bigger, as determined by the their orbital velocities. (ANI)

‘Burping’ astrophysical jets recreated by plasma experiment

London, Feb 21 (ANI): A plasma experiment by scientists has recreated jets of charged particles for the first time in a laboratory, which could shed light on the behaviour of ‘burping’ astrophysical jets from stars and galaxies.

Astrophysical jets are among the largest and most energetic objects in the universe.

The matter inside them travels at nearly the speed of light from colossal black holes at the centres of galaxies. Smaller jets spew at lower speeds from young stars surrounded by discs of gas and dust.

Theorists don’t know exactly how jets form, but they believe the particles inside them are accelerated by magnetic fields, which could be whipped up as matter rotates around a star or black hole.

But, the magnetic fields that seem to keep jets focused can also form kinks that can destabilize the beams, raising questions about how the jets can remain tightly focused over very long distances.

Jets are also clumpy and seem to throw out material in bursts.

“They’re very inhomogeneous with lots of blobs, and it’s very clear that the jet turns on and off,” said Eric Blackman, an astrophysicist at the University of Rochester.

The source of this episodic behaviour is not clear.

But now, according to a report in New Scientist, Blackman and colleagues, led by plasma physicist Andrea Ciardi of the Ecole Normal Superieure in Paris, have recreated the intermittent behaviour that seems to create the clumps seen in telescopes.

“This is the first time we can actually produce episodic behaviour. The experiment shows jets can propagate very far, but they can be quite unstable at the source,” Ciardi told New Scientist.

To create a sequence of bursts, Andrea Ciardi and colleagues fed more than 100 billion watts of power into electrodes connected by a sheet of aluminium foil.

The current created a coiled magnetic field above the foil. It also burned a hole in the foil, turning the aluminium into a soup of charged particles called a plasma.

Because charged particles are accelerated in the presence of a magnetic field, the plasma then sped through the magnetic loop at hundreds of kilometres per second – comparable to speeds seen in stellar jets.

As the first jet was propelled away, more aluminum plasma that had burned off the foil moved in to take its place, and a new jet formed.

The team found that the magnetic environment left over from previous jets seems to stabilize and focus the next jet.

The flows that can be modelled by computer tend to be slow and cool.

Pudritz notes that experiments like this one can get a bit closer to simulating extreme astrophysical conditions, where it is not possible to measure the configuration of magnetic fields. (ANI)

‘Burping’ astrophysical jets recreated by plasma experiment

London, Feb 21 (ANI): A plasma experiment by scientists has recreated jets of charged particles for the first time in a laboratory, which could shed light on the behaviour of ‘burping’ astrophysical jets from stars and galaxies.

Astrophysical jets are among the largest and most energetic objects in the universe.

The matter inside them travels at nearly the speed of light from colossal black holes at the centres of galaxies. Smaller jets spew at lower speeds from young stars surrounded by discs of gas and dust.

Theorists don’t know exactly how jets form, but they believe the particles inside them are accelerated by magnetic fields, which could be whipped up as matter rotates around a star or black hole.

But, the magnetic fields that seem to keep jets focused can also form kinks that can destabilize the beams, raising questions about how the jets can remain tightly focused over very long distances.

Jets are also clumpy and seem to throw out material in bursts.

“They’re very inhomogeneous with lots of blobs, and it’s very clear that the jet turns on and off,” said Eric Blackman, an astrophysicist at the University of Rochester.

The source of this episodic behaviour is not clear.

But now, according to a report in New Scientist, Blackman and colleagues, led by plasma physicist Andrea Ciardi of the Ecole Normal Superieure in Paris, have recreated the intermittent behaviour that seems to create the clumps seen in telescopes.

“This is the first time we can actually produce episodic behaviour. The experiment shows jets can propagate very far, but they can be quite unstable at the source,” Ciardi told New Scientist.

To create a sequence of bursts, Andrea Ciardi and colleagues fed more than 100 billion watts of power into electrodes connected by a sheet of aluminium foil.

The current created a coiled magnetic field above the foil. It also burned a hole in the foil, turning the aluminium into a soup of charged particles called a plasma.

Because charged particles are accelerated in the presence of a magnetic field, the plasma then sped through the magnetic loop at hundreds of kilometres per second – comparable to speeds seen in stellar jets.

As the first jet was propelled away, more aluminum plasma that had burned off the foil moved in to take its place, and a new jet formed.

The team found that the magnetic environment left over from previous jets seems to stabilize and focus the next jet.

The flows that can be modelled by computer tend to be slow and cool.

Pudritz notes that experiments like this one can get a bit closer to simulating extreme astrophysical conditions, where it is not possible to measure the configuration of magnetic fields. (ANI)

‘Burping’ astrophysical jets recreated by plasma experiment

London, Feb 21 (ANI): A plasma experiment by scientists has recreated jets of charged particles for the first time in a laboratory, which could shed light on the behaviour of ‘burping’ astrophysical jets from stars and galaxies.

Astrophysical jets are among the largest and most energetic objects in the universe.

The matter inside them travels at nearly the speed of light from colossal black holes at the centres of galaxies. Smaller jets spew at lower speeds from young stars surrounded by discs of gas and dust.

Theorists don’t know exactly how jets form, but they believe the particles inside them are accelerated by magnetic fields, which could be whipped up as matter rotates around a star or black hole.

But, the magnetic fields that seem to keep jets focused can also form kinks that can destabilize the beams, raising questions about how the jets can remain tightly focused over very long distances.

Jets are also clumpy and seem to throw out material in bursts.

“They’re very inhomogeneous with lots of blobs, and it’s very clear that the jet turns on and off,” said Eric Blackman, an astrophysicist at the University of Rochester.

The source of this episodic behaviour is not clear.

But now, according to a report in New Scientist, Blackman and colleagues, led by plasma physicist Andrea Ciardi of the Ecole Normal Superieure in Paris, have recreated the intermittent behaviour that seems to create the clumps seen in telescopes.

“This is the first time we can actually produce episodic behaviour. The experiment shows jets can propagate very far, but they can be quite unstable at the source,” Ciardi told New Scientist.

To create a sequence of bursts, Andrea Ciardi and colleagues fed more than 100 billion watts of power into electrodes connected by a sheet of aluminium foil.

The current created a coiled magnetic field above the foil. It also burned a hole in the foil, turning the aluminium into a soup of charged particles called a plasma.

Because charged particles are accelerated in the presence of a magnetic field, the plasma then sped through the magnetic loop at hundreds of kilometres per second – comparable to speeds seen in stellar jets.

As the first jet was propelled away, more aluminum plasma that had burned off the foil moved in to take its place, and a new jet formed.

The team found that the magnetic environment left over from previous jets seems to stabilize and focus the next jet.

The flows that can be modelled by computer tend to be slow and cool.

Pudritz notes that experiments like this one can get a bit closer to simulating extreme astrophysical conditions, where it is not possible to measure the configuration of magnetic fields. (ANI)

‘Burping’ astrophysical jets recreated by plasma experiment

London, Feb 21 (ANI): A plasma experiment by scientists has recreated jets of charged particles for the first time in a laboratory, which could shed light on the behaviour of ‘burping’ astrophysical jets from stars and galaxies.

Astrophysical jets are among the largest and most energetic objects in the universe.

The matter inside them travels at nearly the speed of light from colossal black holes at the centres of galaxies. Smaller jets spew at lower speeds from young stars surrounded by discs of gas and dust.

Theorists don’t know exactly how jets form, but they believe the particles inside them are accelerated by magnetic fields, which could be whipped up as matter rotates around a star or black hole.

But, the magnetic fields that seem to keep jets focused can also form kinks that can destabilize the beams, raising questions about how the jets can remain tightly focused over very long distances.

Jets are also clumpy and seem to throw out material in bursts.

“They’re very inhomogeneous with lots of blobs, and it’s very clear that the jet turns on and off,” said Eric Blackman, an astrophysicist at the University of Rochester.

The source of this episodic behaviour is not clear.

But now, according to a report in New Scientist, Blackman and colleagues, led by plasma physicist Andrea Ciardi of the Ecole Normal Superieure in Paris, have recreated the intermittent behaviour that seems to create the clumps seen in telescopes.

“This is the first time we can actually produce episodic behaviour. The experiment shows jets can propagate very far, but they can be quite unstable at the source,” Ciardi told New Scientist.

To create a sequence of bursts, Andrea Ciardi and colleagues fed more than 100 billion watts of power into electrodes connected by a sheet of aluminium foil.

The current created a coiled magnetic field above the foil. It also burned a hole in the foil, turning the aluminium into a soup of charged particles called a plasma.

Because charged particles are accelerated in the presence of a magnetic field, the plasma then sped through the magnetic loop at hundreds of kilometres per second – comparable to speeds seen in stellar jets.

As the first jet was propelled away, more aluminum plasma that had burned off the foil moved in to take its place, and a new jet formed.

The team found that the magnetic environment left over from previous jets seems to stabilize and focus the next jet.

The flows that can be modelled by computer tend to be slow and cool.

Pudritz notes that experiments like this one can get a bit closer to simulating extreme astrophysical conditions, where it is not possible to measure the configuration of magnetic fields. (ANI)

‘Burping’ astrophysical jets recreated by plasma experiment

London, Feb 21 (ANI): A plasma experiment by scientists has recreated jets of charged particles for the first time in a laboratory, which could shed light on the behaviour of ‘burping’ astrophysical jets from stars and galaxies.

Astrophysical jets are among the largest and most energetic objects in the universe.

The matter inside them travels at nearly the speed of light from colossal black holes at the centres of galaxies. Smaller jets spew at lower speeds from young stars surrounded by discs of gas and dust.

Theorists don’t know exactly how jets form, but they believe the particles inside them are accelerated by magnetic fields, which could be whipped up as matter rotates around a star or black hole.

But, the magnetic fields that seem to keep jets focused can also form kinks that can destabilize the beams, raising questions about how the jets can remain tightly focused over very long distances.

Jets are also clumpy and seem to throw out material in bursts.

“They’re very inhomogeneous with lots of blobs, and it’s very clear that the jet turns on and off,” said Eric Blackman, an astrophysicist at the University of Rochester.

The source of this episodic behaviour is not clear.

But now, according to a report in New Scientist, Blackman and colleagues, led by plasma physicist Andrea Ciardi of the Ecole Normal Superieure in Paris, have recreated the intermittent behaviour that seems to create the clumps seen in telescopes.

“This is the first time we can actually produce episodic behaviour. The experiment shows jets can propagate very far, but they can be quite unstable at the source,” Ciardi told New Scientist.

To create a sequence of bursts, Andrea Ciardi and colleagues fed more than 100 billion watts of power into electrodes connected by a sheet of aluminium foil.

The current created a coiled magnetic field above the foil. It also burned a hole in the foil, turning the aluminium into a soup of charged particles called a plasma.

Because charged particles are accelerated in the presence of a magnetic field, the plasma then sped through the magnetic loop at hundreds of kilometres per second – comparable to speeds seen in stellar jets.

As the first jet was propelled away, more aluminum plasma that had burned off the foil moved in to take its place, and a new jet formed.

The team found that the magnetic environment left over from previous jets seems to stabilize and focus the next jet.

The flows that can be modelled by computer tend to be slow and cool.

Pudritz notes that experiments like this one can get a bit closer to simulating extreme astrophysical conditions, where it is not possible to measure the configuration of magnetic fields. (ANI)