Recommended Posts

Posted just a few minutes ago!

Astronomers photographed a cosmic event this morning which they believe is the birth of a black hole, SPACE.com has learned.

A faint visible-light flash likely heralds the merger of two dense neutron stars to create a relatively low-mass black hole, said Neil Gehrels of NASA's Goddard Space Flight Center. It is the first time an optical counterpart to a very short-duration gamma-ray burst has ever been detected.

Gamma rays are the most energetic form of radiation on the electromagnetic spectrum, which also includes X-rays, light and radio waves.

The merger occurred 2.2 billion light-years away, so it actually took place 2.2 billion years ago and the light just reached Earth this morning.

Quick global effort

Gehrels said the burst occurred just after midnight East Coast time. It was detected by NASA's orbiting Swift telescope. Swift automatically repositioned itself within 50 seconds to image the same patch of sky in X-rays. It just barely caught an X-ray afterglow, Gehrels said in a telephone interview.

The X-ray counterpart was barely detectable and only observed for a few hundred seconds.

An email was sent out to astronomers worldwide, and large observatories then tracked to the location spotted a visible-light afterglow.

Gamma ray bursts are mysterious beasts. They come from all over the universe. Long-duration bursts, lasting a few seconds, are thought to be associated with the formation of black holes when massive stars explode and collapse. In recent years, scientists have detected X-ray and optical afterglows of these long bursts.

Very short-duration bursts, like the one this morning, last only a tiny fraction a second. Until now, no optical afterglows from these bursts have been detected. Theorists think the burst represent the formation of a black hole a few times the mass of the Sun, but if so, then there should be bursts of X-rays and visible light, too.

The burst has been named GRB050509b.

What happened

Steinn Sigurdsson, a Penn State University researcher who is excited about the observations but was not involved in them, explained what theorists think happened:

Over a long time period, at least a hundred million years and perhaps billions of years, the two neutron stars spiraled toward each other. Neutron stars themselves are very dense objects, collapsed stellar remnants.

"A fraction of a second before contact, the lower mass neutron star is disrupted and forms a neutrino driven accretion disk around the higher mass neutron star," Sigurdsson told SPACE.com. "It implodes under the weight and forms a maximally spinning low-mass black hole."

Astronomers can't see black holes, because light and everything else that enters them is lost to observation. But just before material falls in, some high-energy process -- likely involving magnetism and speeds approach that of light -- vents some of the material back into space.

The gamma ray burst signals the formation of a superheated jet of gas being shot out from the chaotic region around the newly formed black hole at a significant fraction of light-speed, Sigurdsson said.

"This really does look like a merger scenario," said Gehrels, who heads up the scientific operations for the Swift satellite.

The first gamma-ray burst was detected by accident in 1967. It was found by U.S. satellites deployed to monitor possible violations of the nuclear test ban treaty. Researchers now know that one erupts roughly every day somewhere in the cosmos. Most originate many billions of light years away.

Each burst can briefly outshine an entire galaxy.

space.com

  • 3 weeks later...
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • My father still uses a programme written in dbase3. Still manages to work with a little help from dosbox. 
    • Microsoft hides these secret Windows 11 performance boost settings available on every PC by Sayan Sen Windows enthusiasts often look for ways to extract as much performance out of their systems as possible, and it's often the case that they try and do so while trying to minimize the heat and power consumption. This is especially relevant in the case of mobile Windows PCs since laptops and notebooks tend to get hot and management of that heat and power is harder in such a form factor. As such users often turn to techniques like under-volting which can be used to squeeze out the maximum capabilities of a chip while also maintaining lowered power levels. There are official apps from AMD and Intel with the likes of Ryzen Master and XTU (Extreme Tuning Utility). While these are quite handy, most enthusiasts probably prefer to dig into the BIOS and play around with settings there like Curve Optimizer on Ryzen, which lets users set various frequency-voltage scaling values. These are essentially called P-States. If you are not familiar with them, Processor Power Management is done through Advanced Configuration and Power Interface (ACPI) P-states and C-states. While P-states or performance pwoer states handle CPU voltage-frequency scaling, C-states deal with CPU sleep states so that some of the CPU functions, which are not necessary at that moment, can be disabled. The P-states and C-states work together to make the processor run more efficiently. It helps the OS and apps determine which cores can be parked and which should be boosted. Of course not every user is an enthusiast or knows the technicalities and integrities of how things like overclocking or undervolting work. Thankfully for them Windows itself offers something pretty cool, though it is hidden by default on all systems. By default, Windows only has two P-States, "Minimum Processor State" and "Maximum Processor State." However, this can be changed with a Registry trick to expand the options under a secret "Processor performance boost mode" dropdown. This essentially enables the HWP or hardware P-States available on a device, and these are not controlled just by the OS itself as the underlying hardware gets involved too. In total there are five Processor Performance Boost Mode profiles that control how Windows requests and allows CPU turbo/boost behavior under the different power policies. They are: Disabled: In this mode, processor boosting is effectively turned off. The CPU will avoid entering turbo or boost frequencies and instead operate closer to its base frequency ceiling. This can significantly reduce power consumption and heat output, but at the cost of reduced burst performance and responsiveness in short workloads. Enabled: This is the standard behavior where boost functionality is allowed under normal conditions. The processor can opportunistically increase frequency when workload demands it, balancing performance gains with power and thermal constraints as managed by the system. Aggressive: Aggressive mode favors performance more heavily, allowing the CPU to enter higher boost states more readily and sustain them longer. This should in theory improve responsiveness under bursty or heavy workloads but increases power draw and thermal output compared to the default enabled behavior. Efficient Enabled: This mode still allows boosting, but with a stronger bias toward energy efficiency. The system attempts to use boost more selectively, avoiding unnecessary frequency spikes when the performance gain is marginal. Efficient Aggressive: This is a hybrid approach where boost is still performance-responsive, but the system continuously weighs efficiency more heavily than in Aggressive mode. It aims to deliver noticeable performance improvements while reducing wasted power in less demanding scenarios. Here's how to enable the Processor performance boost mode: Open Registry Editor: Press Win+R, type regedit, and click OK. Go to: HKLM\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\54533251-82be-4824-96c1-47b60b740d00\be337238-0d82-4146-a960-4f3749d470c7 (where HKLM stands for HKEY_LOCAL_MACHINE_) Modify the value of Attributes from 1 to 2 (you can find modify option by right-clicking) After that, exit Registry, you should now be able to see the new "Processor performance boost mode" dropdown menu: As you can see there are now five new P-States or CPPC states or power profile available that help define the boost mode processor setting on your PC. Wrapping it up here's a quick run-down of the settings as defined by Microsoft itself. Setting Description Disabled The corresponding P-state-based behaviour is disabled. Collaborative Processor Performance Control (CPPC) behaviour is disabled. Enabled The corresponding P-state-based behaviour is enabled. CPPC behaviour is Efficient Enabled. Aggressive The corresponding P-state-based behaviour is enabled. CPPC behaviour is Aggressive. Efficient Enabled The corresponding P-state-based behaviour is Efficient. CPPC behaviour is Efficient Enabled. Efficient Aggressive The corresponding P-state-based behaviour is Efficient. CPPC behaviour is Aggressive. Aggressive At Guaranteed Windows calculates the desired extra performance above the guaranteed performance level, and asks the processor to deliver that specific performance level. Efficient Aggressive At Guaranteed Windows always asks the processor to deliver the highest possible performance above the guaranteed performance level. In the next part we shall be comparing these settings to explore how much of a benefit or regression they can provide in terms of performance and power efficiency. If you decide to change the values on your system and are experiencing problems like crashes or an overheating PC, make sure to revert the steps back to the original state.
    • I think he means you haven't reviewed previous UFC games. Of course it doesn't matter... Every time you just report on something that involves the President even if just simply what happened you guys usually get accused of being anti-Trump. We live in fun times.
  • Recent Achievements

    • One Month Later
      Leroy Jethro Gibbs earned a badge
      One Month Later
    • Conversation Starter
      flexorcist earned a badge
      Conversation Starter
    • One Month Later
      AndreaB earned a badge
      One Month Later
    • One Month Later
      agatameier earned a badge
      One Month Later
    • Week One Done
      agatameier earned a badge
      Week One Done
  • Popular Contributors

    1. 1
      +primortal
      518
    2. 2
      +Edouard
      198
    3. 3
      PsYcHoKiLLa
      147
    4. 4
      ATLien_0
      93
    5. 5
      Steven P.
      77
  • Tell a friend

    Love Neowin? Tell a friend!