Tag Archives: XRay

Exploring the World’s Most Advanced X-Ray Machine: Journey Before Its Power Boost

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Electron beam traversing a niobium cavity, integral to SLAC's LCLS-II X-ray laser.

Electron Beam in Niobium Cavity: A Core Element of SLAC’s LCLS-II X-ray Laser

Credit: SLAC National Accelerator Laboratory

The Klystron Gallery at SLAC National Accelerator Laboratory is a concrete corridor lined with robust metal columns that stretch well beyond my line of sight. Yet, beneath this unassuming structure lies a marvel of modern science.

Below the gallery, the Linac Coherent Light Source II (LCLS-II) extends over an impressive 3.2 kilometers. This cutting-edge machine produces X-ray pulses that are the strongest in the world. I am here to witness it because a significant record has just been surpassed. However, an upgrade is set to take its most powerful component offline soon. When it reopens—anticipated as early as 2027—it will more than double its X-ray energy output.

“It’s like the difference between a star’s twinkle and the brightness of a light bulb,” says James Cryan at SLAC.

Dismissing LCLS-II as merely a sparkle would be profoundly misleading. In 2024, it achieved the most potent X-ray pulse ever recorded. Although it lasted a mere 440 billionths of a second, it released nearly 1 terawatt of energy—far surpassing the annual output of a typical nuclear power plant. Moreover, in 2025, LCLS-II set a record of generating 93,000 X-ray pulses per second, a remarkable feat for an X-ray laser.

According to Cryan, this milestone enables researchers to undertake groundbreaking studies of how particles behave within molecules after absorbing energy. It’s akin to transforming a black-and-white film into a vibrant, colorful cinematic experience. With this breakthrough and forthcoming enhancements, LCLS-II has the capacity to revolutionize our understanding of the subatomic behavior of light-sensitive systems, from photosynthetic organisms to advanced solar cell technologies.

LCLS-II operates by accelerating electrons toward near-light speeds—the ultimate velocity threshold in physics. The cylindrical device known as the klystron, which gives the klystron gallery its name, generates the microwaves necessary for this acceleration. Once the electrons attain sufficient speed, they navigate through arrays of thousands of strategically placed magnets, enabling their oscillation and producing an X-ray pulse. These pulses can be utilized for imaging the internal structure of various materials, similar to medical X-rays.

During my visit, I had the opportunity to tour one of several experimental halls. Here, the X-ray pulses collide with molecules, enabling a closer look at their interactions. These experimental areas resemble futuristic submarines—with heavy metal exteriors and large glass windows—engineered to exclude stray air molecules that could disrupt their experiments.

Just before my visit, Cryan and his team conducted an experiment to examine proton movements within molecules. Traditional imaging techniques struggle to provide detailed insight into proton dynamics, yet these specifics are vital for advancing solar cell technology, Cryan emphasizes.

What awaits these investigations post-upgrade when LCLS-II evolves into LCLS-II-HE? Cryan states that the enhanced capability to examine particle behavior within molecules will be significantly augmented. However, the path to upgrades is challenging.

Explore CERN: The Hub of Particle Physics in Europe

Get ready to explore CERN, Europe’s premier center for particle physics, nestled near the beautiful city of Geneva, Switzerland, famous for housing the Large Hadron Collider.

John Schmage from SLAC notes that as the energy of the electron beam increases, the risk of particles straying becomes a significant concern. He recounts witnessing a misbehaving beam damage equipment at another facility, highlighting the necessity for precision. SLAC’s Ding Yuantao emphasizes that all new components installed during the upgrade are designed to endure higher power outputs, but they must increase energy levels gradually to ensure operational integrity. “We’ll activate the beam and closely monitor its performance,” he states.

In 2026, the team plans to engage in a significant engineering initiative to align the components, followed by one to two years of meticulous setup for a staged increase in power output. If all progresses according to plan, the upgraded LCLS-II-HE will be available for global researchers by 2030. Ongoing communication between X-ray users like Cryan, and operators like Schmage and Ding, will be essential. “This tool will evolve, and we will continually enhance its capabilities,” Schmage notes.

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Source: www.newscientist.com

XMM-Newton Delivers Incredible X-Ray Images of Interstellar Comet 3I/ATLAS

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Astronomers utilizing ESA’s XMM-Newton Observatory have captured X-ray images of 3I/ATLAS, the third confirmed interstellar object to traverse our solar system, following 1I/Oumuamua and 2I/Borisov.

This XMM-Newton image displays an X-ray visualization of the interstellar comet 3I/ATLAS. The center features a bright red dot against a dark backdrop, resembling a burning lighthouse. Surrounding this core is a soft gradient of purple and blue, forming a slightly rotated rectangular frame divided by a thin horizontal line, indicating the detector gap. Red represents low-energy X-rays, while blue signifies regions with minimal X-rays. Image credit: ESA / XMM-Newton / C. Lisse / S. Cabot / XMM ISO Team.

On December 3, 2025, XMM-Newton tracked the interstellar comet 3I/ATLAS for approximately 20 hours.

During this observation, the interstellar object was about 282-285 million kilometers away from the spacecraft.

XMM-Newton utilized the European Photon Imaging Camera (EPIC)-PN, its most sensitive X-ray camera, to observe the comet.

“This XMM-Newton image highlights the comet radiating in low-energy X-rays. The blue regions indicate voids with nearly no X-rays, while the red areas showcase the comet’s X-ray emissions,” stated members of the XMM-Newton team.

Astronomers anticipated this glow, as gas molecules emitted from comets generate X-rays upon colliding with the solar wind.

“These X-rays can originate from the interaction of the solar wind with gases such as water vapor, carbon dioxide, and carbon monoxide, and have previously been detected by telescopes like NASA/ESA/CSA’s James Webb Space Telescope and NASA’s SPHEREx,” added the researchers.

“However, these telescopes possess distinct sensitivities to gases like hydrogen and nitrogen.”

“They are almost undetectable by optical and ultraviolet instruments, such as the NASA/ESA Hubble Space Telescope and ESA’s JUICE camera.”

“This makes X-ray observation an exceptional resource,” they emphasized.

“Researchers will be able to identify and examine gases that are difficult to detect with alternative instruments.”

“Multiple scientific groups suggest that the first observed interstellar object, 1I/’Oumuamua, may have been composed of unusual ices like nitrogen and hydrogen.”

“Although 1I/Oumuamua is currently too distant to study, 3I/ATLAS provides fresh opportunities to investigate interstellar bodies. X-ray observations will supplement other data and assist scientists in understanding the composition of these objects.”

Source: www.sci.news

X-ray Enhanced Fabric Potentially Alleviates Mammogram Discomfort

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Mammograms can be painful,

Dahlia Artemenko/Alamie

Getting X-rays can be quite uncomfortable. You might need to lie still while experiencing discomfort or as a part of your body is compressed. However, innovative flexible fabrics that enhance X-ray detection could alleviate this issue.

“Picture scanning your child for injuries and conducting a painless breast examination without requiring the child to stay still,” says Li Xu from the Hong Kong Institute of Technology. She and her team have developed a fabric known as X-Wear, which emits light when exposed to X-rays.

X-rays typically utilize scintillation components, which are harder to detect than visible light, in both medical and industrial applications. For example, they can convert rays that penetrate your limbs into visible light, allowing for the creation of images that reveal internal details like fractures. However, the current scintillators are usually rigid, which makes them uncomfortable for use in devices where they are embedded.

To tackle this issue, researchers have reformulated scintillating materials, like reshaping gadolinium oxide sprinkled with europium into fine fibers, which are then integrated into fabrics.

Xu mentions that crafting these fibers to be flexible while ensuring they emit sufficient light for producing high-resolution images when exposed to X-rays poses a technical challenge. Her team has demonstrated that fabrics can be utilized for dental X-rays – in tests, X-Wear adapted to the shape of a clay mouth model and teeth. It has also been used for mammography, where an X-Wear bra was created to eliminate the need for compressing a person’s breasts during imaging, a common current practice.

Imalka Jayawardena from the University of Surrey in the UK emphasizes that X-Wear’s body-compliant nature is a significant advantage over other flexible scintillator designs, which tend to be film-like and inflexible. However, he notes that the light detectors paired with X-Wear are still flat, limiting the fabric’s potential applications.

Currently, researchers can produce about a quarter of a square meter of X-Wear samples, meaning production must be scaled up and adapted for industrial-grade equipment before it can be used widely, according to Xu.

The team is also exploring X-Wear’s potential for industrial use, envisioning small, flexible devices for inspecting electronics and identifying defects in pipelines. Xu also notes that first responders in disaster zones could utilize X-Wear, equipped with smartphones and compact X-ray sources, for conducting on-site scans.

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Source: www.newscientist.com

IXPE Measures X-Ray Polarization from Magnetic Explosions

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A magnetor is a type of neutron star that boasts an extraordinarily strong magnetic field, approximately one times stronger than Earth’s magnetic field. These colossal magnetic fields are believed to be generated when rapidly rotating neutron stars are birthed from the collapse of a giant star’s core. Magnetars emit brilliant X-rays and display erratic patterns of activity, with bursts and flares releasing millions of times more energy than the Sun emits in just one second. Polarization measurements offer insights into magnetic fields and surface characteristics. This was the focus of astronomers using the NASA Imaging X-ray Polarization Explorer (IXPE) to study 1E 1841-045, a magnetor located within Supernova Remnant (SNR) KES 73, situated nearly 28,000 light years from Earth. The findings are published in the Astrophysics Journal Letter.

Impressions of Magneter artists. Image credit: NASA’s Goddard Space Flight Center/S. Wesinger.

Magnetors represent a category of young neutron stars. They are the remnants of giant stars that collapsed in on themselves at the end of their life cycles, resembling the mass of the Sun but compressed into a city-sized volume.

Neutron stars exemplify some of the most extreme physical conditions in the observable universe, offering a unique chance to investigate states that cannot be replicated in terrestrial laboratories.

The 1E 1841-045 magnetor was observed in an explosive state on August 21, 2024, by NASA’s Swift, Fermi, and other advanced telescopes.

The IXPE team has permitted several requests to pause scheduled observations of the telescope multiple times each year, redirecting focus to unique and unexpected celestial phenomena.

When 1E 1841-045 transitioned into this bright active phase, scientists chose to direct IXPE to capture the first polarization measurements of the magnetor’s flare.

Magnetors possess magnetic fields thousands of times stronger than most neutron stars, hosting the most powerful magnetic fields among known cosmic entities.

These extreme magnetic field fluctuations can lead to the emission of X-ray energies up to 1,000 times greater than usual for several weeks.

This heightened state is referred to as explosive activity, though the underlying mechanisms remain poorly understood.

IXPE’s X-ray polarization measurements may help unveil the mysteries behind these phenomena.

Polarized light carries information about the direction and orientation of emitted X-ray waves. A higher degree of polarization indicates that the X-ray waves are moving in harmony, akin to a tightly choreographed dance.

Studying the polarization characteristics of magnetors provides clues regarding the energy processes associated with observed photons and the direction and configuration of the magnetor’s magnetic field.

This diagram illustrates the IXPE measurements of X-ray polarized light emitted by 1E 1841-045. Image credit: Michela Rigoselli / Italian National Institute of Astrophysics.

IXPE results, supported by NASA’s Nustar and other telescope observations, indicate that X-ray emissions from 1E 1841-045 exhibit increased polarization at higher energy levels while maintaining a consistent emission direction.

This significant contribution to the high degree of polarization is attributed to the hard X-ray tail of 1E 1841-045, a highly energetic component of the magnetosphere responsible for the highest photon energies detected by IXPE.

Hard X-rays refer to X-rays characterized by shorter wavelengths and greater energy than soft X-rays.

While prevalent in magnetars, the processes that facilitate the generation of these high-energy X-ray photons remain largely enigmatic.

Despite several proposed theories explaining this emission, the high polarization associated with these hard X-rays currently offers additional clues to their origins.

“This unique observation enhances existing models that aim to explain magnetic hard X-ray emissions by elucidating the extensive synchronization seen among these hard X-ray photons,” remarked a student from George Washington University. First paper.

“This effectively demonstrates the power of polarization measurements in refining our understanding of the physics within a magnetar’s extreme environment.”

“It would be fascinating to observe 1E 1841-045 as it returns to its stable baseline state and to track the evolution of polarization,” added Dr. Michela Rigoselli, an astronomer at the National Institute of Astrophysics in Italy. Second paper.

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Rachel Stewart et al. 2025. X-ray polarization of Magnetor 1E 1841-045. apjl 985, L35; doi: 10.3847/2041-8213/adbffa

Michela Rigoselli et al. 2025. IXPE detection of highly polarized X-rays from Magnetor 1E 1841-045. apjl 985, L34; doi: 10.3847/2041-8213/adbffb

Source: www.sci.news

Radio Waves and X-ray Emitting Stars: A New Perspective from Our Galaxy

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Askap J1832-0911 – Likely a magnetar or a highly magnetized white dwarf star – emits radio signals and X-ray pulses for 2 minutes every 44 minutes. Paper published in Nature.

A combination of radio, X-ray, and infrared radiation in the field of ASKAP J1832-0911. Image credit: Wang et al., doi: 10.1038/S41586-025-09077-W.

Askap J1832-0911 is situated roughly 15,000 light-years away from Earth in Scutum.

This star was identified by astronomers utilizing the Australian ASKAP Radio telescope.

It belongs to a category known as long-term radio transients, first detected in 2022, characterized by variations in radio wave intensity over several minutes.

This duration is thousands of times greater than the regular fluctuations observed in pulsars. It’s a neutron star that spins rapidly, emitting signals multiple times per second.

“Askap J1832-0911 follows a 44-minute cycle of radio wave intensity, placing it in the realm of long-term radio transients,” stated Dr. Ziteng Wang, an astronomer at Curtin University’s node at the International Centre for Radio Astronomical Research (ICRAR).

Using NASA’s Chandra X-Ray Observatory, researchers noted that ASKAP J1832 also exhibited regular variations in X-ray emissions every 44 minutes.

This marks the first discovery of an X-ray signal in long-term radio transients.

“Astronomers have observed countless celestial bodies through various telescopes and have never encountered anything behaving like this,” Dr. Wang remarked.

“It’s exhilarating to witness such new stellar phenomena.”

Through Chandra and the SKA Pathfinder, scientists found that Askap J1832-0911 experienced a significant reduction in both X-ray and radio wave signals over a six-month period.

Besides the long-term changes, the combination of 44-minute cycles in X-rays and radio waves differs from observations made in the Milky Way galaxy.

The authors are currently competing to determine whether Askap J1832-0911 truly represents long-term radio transients and if its unusual behavior can shed light on the origins of such objects.

Dr. Nanda Lea, an astronomer at the Institute of Space Sciences in Barcelona, Spain, commented:

“No exact match has been found so far, but some models fit better than others.”

It’s improbable that ASKAP J1832-0911 is simply a pulsar or neutron star drawn from a companion star, as its properties do not align with the typical signal strengths of these celestial objects.

Some characteristics might be attributed to neutron stars with exceptionally strong magnetic fields, known as magnetars, which are over 500,000 years old.

However, other aspects, such as its bright and variable radio emissions, make it challenging to categorize this as an aged magnetar.

In the sky, ASKAP J1832-0911 appears to be situated among debris from a supernova, which commonly contains neutron stars formed during such events.

Nevertheless, the team concluded that this proximity is likely coincidental and that the two entities are not associated with one another, suggesting that neither may host neutron stars.

They deduced that while isolated white dwarfs don’t account for the data, white dwarfs with companion stars might.

But such a scenario would necessitate the strongest known magnetic fields in white dwarfs within our galaxy.

“We continue to seek clues about this object and look for similar entities,” said Dr. Tong Bao, an astronomer at the Osservatorio Astronomico in Italy’s National Institute of Astronomy (INAF).

“Discovering mysteries like this is not frustrating; rather, it’s what makes science thrilling!”

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Z. Wang et al. Detection of X-ray radiation from bright long-term radio transients. Nature Published online on May 28, 2025. doi:10.1038/s41586-025-09077-W

Source: www.sci.news

The Interaction of Fast-Moving Electrons and Photons Drives X-Ray Emission in Blazar Jets

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A recent study utilized NASA’s IXPE (Imaging X-ray Polarized Explorer) to analyze a highly relativistic jet originating from the Blazar Bl Lacertae, a supermassive black hole surrounded by luminous discs.

This artist’s rendering illustrates the core area of Blazar Bl Lacertae, featuring an ultra-massive black hole surrounded by bright discs and Earth-directed jets. Image credit: NASA/Pablo Garcia.

Astrophysicists elucidated a highly relativistic jet, proposing two competing theories regarding an X-ray component made up of protons and electrons.

Each theory presents a distinct signature in the polarization characteristics of the X-ray light.

Polarized light signifies the average direction of the electromagnetic waves comprising light.

When X-rays in a black hole’s jets are highly polarized, it indicates production from protons that circulate within the magnetic field of the jet or protons interacting with the jet’s photons.

Conversely, low polarization in X-rays implies that the generation of X-rays occurs through electron-photon interactions.

The IXPE is the sole satellite capable of making such polarization measurements.

“This was one of the greatest mysteries involving supermassive black hole jets,” remarks Dr. Ivan Agdo, an astronomer at Astrophicidae Athtrophicidae and Andocia-CSIC.

“Thanks to numerous supporting ground telescopes, IXPE equipped us with the necessary tools to ultimately resolve this issue.”

Astronomers concluded that electrons are likely the source, through a process known as Compton scattering.

This phenomenon, also referred to as the Compton effect, occurs when photons lose or gain energy through interactions with charged particles (primarily electrons).

Within the jets of a supermassive black hole, electrons move at speeds approaching that of light.

IXPE enabled researchers to determine that, in Blazar jets, electrons possess enough energy to scatter infrared photons into the X-ray spectrum.

Bl Lacertae, one of the earliest discovered Blazars, was initially thought to be a kind of star in the Lacerta constellation.

IXPE monitored Bl Lacertae for seven days in November 2023, in conjunction with several ground-based telescopes also measuring optical and radio polarization.

Interestingly, during the X-ray polarization observations, Bl Lacertae’s light polarization peaked at 47.5%.

“This marks not only the most polarized BL Lacertae has been in the past 30 years, but indeed the highest ever recorded,” states Dr. Ioannis Riodakis, an astrophysicist at the Institute of Astrophysics.

Researchers noted that X-rays are significantly less polarized than optical light.

They were unable to detect strong polarized signals and ascertained that the X-rays could not exceed 7.6% polarization.

This finding confirms that electron interactions with photons via the Compton effect must account for the X-ray emissions.

“The fact that optical polarization is considerably higher than that of X-rays can only be explained by Compton scattering,” he added.

“IXPE has solved yet another mystery surrounding black holes,” claimed Dr. Enrico Costa, an astrophysicist associated with the planet spaziali of astituto to astituto to n diastrofísica.

“IXPE’s polarized X-ray capabilities have unraveled several long-standing mysteries, which is a significant achievement.

“In other instances, IXPE’s results challenged previously held beliefs, opening up new questions, but that’s the essence of science, and certainly IXPE excels in its scientific contributions.”

Survey results will be published in Astrophysics Journal Letter.

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Ivan Agd et al. 2025. The height of X-ray and X-ray polarization reveals Compton scattering of BL Lacertae jets. apjl in press; doi: 10.3847/2041-8213/ADC572

Source: www.sci.news

Strange X-ray Emissions from a Remote White Dwarf Destroy a Devastated Exoplanet

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Astronomers may have ultimately solved the problem of what is causing the highly energy x-rays of WD 2226-210, a white dwarf star located in the heart of the Helix Nebula.

The impression of this artist shows an ex faction (left) that has come too close to the white dwarf (right) and torn apart by the power of the tide from the stars. Image credits: NASA/CXC/SAO/M. Weiss.

Helix Nebula It is a so-called planetary nebulae, a late stage of the star that discharges the outer layer of gas and leaves behind what is known as the white dwarf.

In the past decades, the Einstein X-ray Observatory and the Rosatt Telescope have detected highly energy x-rays from the white d star of the Helix Nebula, WD 2226-210.

White dwarfs like the WD 2226-210, just 650 light years away, usually do not emit powerful X-rays.

“They're the best,” said Dr. Sandino Estrada Dorado, an astronomer at the National Autonomous University of Mexico.

“We may finally have found the cause of a mystery that lasted over 40 years.”

Previously, astronomers determined that Neptune-sized planets were in very close orbits around WD 2226-210.

Dr. Estrada Dorado and colleagues conclude that there may have been a planet like Jupiter, even closer to the star.

The besieged planet may have initially managed to hold a considerable distance from the white dwarf, but moved inwards by interacting with the gravity of other planets in the system.

Once it got close enough to the white dwarf, the gravity of the star would have partially or completely tore the planet.

“The mystical signals we've seen can be caused by fragments from the crushed planet falling onto the surface of a white dwarf and being heated to shine with x-rays,” said Dr. Martin Guerrero, an astronomer at the Andalusian Institute of Astronomy.

“If confirmed, this will be the first case of a planet that is considered to be destroyed by the central star of the planet.”

WD 2226-210 is located at the heart of the Helix Nebula. Image credit: NASA/CXC/SAO/UNIV MEXICO/ESTRADA-DORADO et al. /JPL/ESA/STSCI/M. MEIXNER/NRAO/TA RECTOR/ESO/Vista/J. Emerson/K. Arcand.

This study shows that X-ray signals from the white d star remained roughly constant in brightness between 1992, 1999 and 2002.

However, this data suggests that there are subtle and regular changes in the x-ray signal every 2.9 hours, which may provide evidence of planetary ruins very close to the white d star.

The author also considered whether a low-mass star could have been destroyed rather than a planet.

Such stars are roughly the same size as planets like Jupiter, but are much less likely to have been torn apart by larger, white dwarfs.

WD 2226-210 has some similarities between the two other white d stars that are not within the planet's nebula and the X-ray behavior.

It may separate the material from the planet's ally, but it will separate the material in a more sedative way without the planet being destroyed immediately.

Other white dwarfs may have dragged material onto their surfaces from traces of the planet.

These three white d stars can form variables or objects of change in the new class.

“They're the best,” said Dr. Jess Tora, an astronomer at the National Autonomous University of Mexico.

Team's paper It will be published in Monthly Notices from the Royal Astronomical Society.

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S. Estrada-Dorado et al. 2025. Added to WD 2226-210, the central star of the Helix Nebula. mnrasin press; Arxiv: 2412.07863

This article is a version of a press release provided by NASA.

Source: www.sci.news

The Tarantula Nebula is captured in the deepest X-ray images ever by Chandra

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The Tarantula Nebula is the most important star-forming complex in local galaxy groups, including the Milky Way, the large Magellan cloud and the Andromeda galaxy. At its heart is the highly rich young star cluster R136, which contains the most huge known stars. The stellar wind and supernova carved the tarantula nebula into an astonishing display of arcs, pillars and bubbles.

This image of Chandra shows the Tarantula Nebula. Image credits: NASA/CXC/Penn State/Townsley et al.

The Tarantula Nebula is approximately 170,000 light years away from the southern constellation of Dorado.

The nebula, also known as the NGC 2070 or 30 Dorados, is part of the large Magellan cloud.

“The Tarantula Nebula is the most powerful and large star-forming region in the local galaxy group,” says Matthew Povich, astronomers at Polytechnic University in California, and Pennsylvania State University astronomers Raysa Townsley and Patrick Brose. I said that.

“The nebulae differ from the massive star-forming regions of the Milky Way galaxy. There is no different galactic rotation to tear the complex, so it provides fuel for at least 25 million years to supply large star-forming. It lasts and grows at the confluence of two super-huge shells, reaching a starburst percentage.”

“Today, it is dominated by a central large cluster R136, 1-2 million years ago, and includes the wealthiest young star population of the local group, and the largest star included It's here.”

“In contrast to the large star-forming regions of the galaxy, the location of the large Magellan tarantula nebula provides a low metallic starburst laboratory with low absorption and well-known distances. I'll do that.”

https://www.youtube.com/watch?v=ivd_gmu9p8c

New X-ray images of the tarantula nebula contain data from the large Chandra program, including observation times of approximately 23 days, with Chandra previously performed in the nebula for over 1.3 days.

The 3,615 x-ray sources detected by Chandra include large stars, double star systems, bright stars still in the process of formation, and much smaller clusters of young stars.

The authors also identified the oldest X-ray pulsar candidate ever detected in Tarantula Nebula, PSR J0538-6902.

“There are a ton of diffuse hot gases found in x-rays that come from various sources that arise from the giant star winds and gases expelled by supernova explosions,” the astronomer said.

“This dataset is ideal for the near future to study diffuse X-ray emissions in star-forming regions.”

Team's paper It will be published in Astrophysical Journal Supplement Series.

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Raysa K. Townsley et al. 2025. TARANTULA – Revealed by X-ray (T-REX). APJin press; Arxiv: 2403.16944

Source: www.sci.news

Mysterious X-ray oscillations detected in supermassive black hole by XMM-Newton

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In 2018, astronomers discovered that the corona of 1ES 1927+654, an actively accreting black hole with 1.4 million solar masses located in a galaxy some 270 million light-years away, suddenly disappeared and reassembled several months later. I observed that. The short but dramatic outage was the first of its kind in black hole astronomy. Now, astronomers using ESA's XMM-Newton Observatory have captured the same black hole exhibiting even more unprecedented behavior. They detected X-ray flashes from 1ES 1927+654 at a steadily increasing clip. Over a two-year period, the frequency of millihertz vibration flashes increased from every 18 minutes to every 7 minutes. This dramatic speed-up of X-rays has never been observed from a black hole before.

In this artist's concept, material is stripped from a white dwarf (bottom right sphere) orbiting within the innermost accretion disk surrounding the supermassive black hole of 1ES 1927+654. Image credit: NASA/Aurore Simonnet, Sonoma State University.

Black holes are a prediction of Albert Einstein's theory of general relativity. They are gravitational monsters that trap any matter or energy that crosses their “surface,” a region of spacetime known as the event horizon.

In its final descent into the black hole, a process known as accretion, the doomed material forms a disk around the black hole. The gas in the accretion disk heats up and emits primarily ultraviolet (UV) light.

The ultraviolet light interacts with the cloud of electrically charged gas or plasma that surrounds the black hole and accretion disk. This cloud is known as the corona, and the interaction energizes the ultraviolet light and amplifies it into X-rays, which can be captured by XMM Newton.

XMM-Newton has been observing 1ES 1927+654 since 2011. Back then, everything was very normal.

But things changed in 2018. As the X-ray corona disappeared, the black hole erupted in a massive explosion that seemed to disrupt its surroundings.

The coronavirus gradually returned, and by early 2021, it seemed like normal conditions had returned.

However, in July 2022, XMM Newton began observing its X-ray output fluctuating at a level of about 10% on timescales of 400 to 1,000 seconds.

This type of fluctuation, called quasi-periodic oscillations (QPO), is notoriously difficult to detect in supermassive black holes.

“This was the first sign that something strange was going on,” said Dr. Megan Masterson. Student at MIT.

The oscillations could suggest that a massive object, such as a star, is embedded in the accretion disk and rapidly orbiting the black hole on its way to being swallowed.

As an object approaches a black hole, the time it takes to orbit decreases and the frequency of its oscillations increases.

Calculations revealed that the orbiting object was probably the remains of a star known as a white dwarf, had about 0.1 times the mass of the Sun, and was moving at an astonishing speed.

It was completing one orbit of the central monster, covering a distance of about 100 million km, about every 18 minutes. Then things got even weirder.

Over nearly two years, XMM Newton showed an increase in the strength and frequency of the vibrations, but not as much as the researchers expected.

They assumed that an object's orbital energy is being emitted as gravitational waves, as prescribed by the theory of general relativity.

To test this idea, they calculated when the object crossed the event horizon, disappeared from view, and stopped oscillating. It turns out to be January 4, 2024.

“Never in my career have I been able to predict anything so accurately,” says Dr. Erin Kara of MIT.

In March 2024, XMM Newton observed it again and the oscillations were still present.

The object was currently traveling at about half the speed of light, completing an orbit every seven minutes.

Whatever was inside the accretion disk, it stubbornly refused to be swallowed up by the black hole.

Either something more than gravitational waves is at play, or the entire hypothesis needs to be changed.

Astronomers also considered other possibilities for the origin of the vibrations.

Remembering that the X-ray corona disappeared in 2018, they wondered if this cloud itself was vibrating.

The problem is that there is no established theory to explain such behavior, so there is no clear path to take this idea further, so they go back to the original model and realize there is a way to fix it. I did.

“If the black hole has a white dwarf companion, the gravitational waves produced by the black hole could be detected by LISA, an ESA mission scheduled to launch within the next 10 years in partnership with NASA.” said Masterson.

team's paper will appear in journal nature.

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Megan Masterson others. 2025. Millihertz oscillations near the innermost orbit of a supermassive black hole. naturein press. arXiv: 2501.01581

Source: www.sci.news

Astronomers Propose that X-ray and Ultraviolet Radiation Impact the Protoplanetary Disk in Cygnus OB2

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Cygnus OB2 is the giant young stellar association closest to the Sun.

In this new composite image, Chandra data (purple) shows the diffuse X-ray emission and young stars of Cygnus OB2, along with infrared data (red, green, blue, cyan) from NASA's now-retired Spitzer Space Telescope reveals young stars. And it creates cold dust and gas throughout the region. Image credits: NASA / CXC / SAO / Drake others. / JPL-California Institute of Technology / Spitzer / N. Walk.

At a distance of approximately 1,400 parsecs (4,600 light years), Cygnus OB2 It is a huge young body closest to the Sun.

It contains hundreds of double stars and thousands of low-mass stars.

Dr. Mario Giuseppe Guarcero of the National Institute of Astrophysics, Dr. Juan Facundo Albacete Colombo of the University of Rio Negro, and colleagues used NASA's Chandra X-ray Observatory to study various regions of Cygnus OB2. observed.

This deep observation mapped the diffuse X-ray glow between the stars and also provided an inventory of young stars within the cluster.

This inventory was combined with other inventories using optical and infrared data to create the best survey of young stars within the association.

“These dense stellar environments are home to large amounts of high-energy radiation produced by stars and planets,” the astronomers said.

“X-rays and intense ultraviolet radiation can have devastating effects on planetary disks and systems that are in the process of forming.”

The protoplanetary disk around the star naturally disappears over time. Part of the disk falls onto the star, and some is heated by X-rays and ultraviolet light from the star and evaporates in the wind.

The latter process, known as photoevaporation, typically takes 5 million to 10 million years for an average-sized star to destroy its disk.

This process could be accelerated if there is a nearby massive star that produces the most X-rays and ultraviolet light.

researchers Found Clear evidence that protoplanetary disks around stars actually die out much faster when they approach massive stars that produce large amounts of high-energy radiation.

Also, in regions where stars are more densely packed, the disk dies out faster.

In the region of Cygnus OB2, which has less high-energy radiation and fewer stars, the proportion of young stars with disks is about 40%.

In regions with higher-energy radiation and more stars, the proportion is about 18%.

The strongest influence, and therefore the worst location for a star to become a potential planetary system, is within about 1.6 light-years of the most massive star in the cluster.

In another study, the same team I looked into it Characteristics of the diffuse X-ray emission of Cygnus OB2.

They discovered that the high-energy, diffuse radiation originates from regions where winds of gas blown from massive stars collide with each other.

“This causes the gas to become hot and generate X-rays,” the researchers said.

“The low-energy release is likely caused by gas within the cluster colliding with gas surrounding the cluster.”

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MG Guarcero others. 2024. Photoevaporation and close encounters: How does the environment around Cygnus OB2 affect the evolution of the protoplanetary disk? APJS 269, 13; doi: 10.3847/1538-4365/acdd67

JF Albacete vs Colombo others. 2024. Diffuse X-ray emission in the Cygnus OB2 coalition. APJS 269, 14;doi: 10.3847/1538-4365/acdd65

Source: www.sci.news

New X-ray Telescope NICER Makes Exciting Discovery of Fast-Spinning Neutron Star

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The neutron star in X-ray binary system 4U 1820-30 rotates 716 times per second, the fastest rate ever observed, according to an analysis of data collected by NASA’s Neutron Star Internal Composition Explorer (NICER). It is one of the rotating celestial bodies. 2017 and 2022.

Artist’s depiction of the X-ray binary star system 4U 1820-30 at the center of globular cluster NGC 6624. Image credit: NASA.

4U 1820-30 It is located approximately 26,000 light years from Earth in the constellation Sagittarius.

This X-ray binary star system is part of a metal-rich globular cluster called NGC6624.

It consists of two stars: a neutron star and a white dwarf companion. The latter orbits a neutron star every 11 minutes, making it the star system with the shortest known orbital period.

The 4U 1820-30 typically displays short bursts of X-rays that last only 10 to 15 seconds. This is likely due to the ignited helium-rich fuel burning out quickly on the surface.

“Due to its strong gravity, the neutron star pulls matter away from its companion star,” said Dr. Gaurava Jaisawal of DTU Space and colleagues.

“When enough material accumulates on the surface, a violent thermonuclear explosion occurs on the neutron star, similar to an atomic bomb.”

Astronomers observed 4U 1820-30 using NASA’s NICER X-ray telescope mounted outside the International Space Station.

“While studying thermonuclear explosions from this system, we discovered significant oscillations, caused by the neutron star rotating around its central axis at an astonishing speed of 716 times per second. “This suggests that the

“If future observations confirm this, the 4U 1820-30 neutron star would be one of the fastest rotating objects ever observed in the universe, rivaled by a star called PSR J1748-2446. There will only be another neutron star.”

From 2017 to 2021, NICER detected 15 thermonuclear X-ray bursts from 4U 1820-30.

This was one of the bursts that exhibited symptoms known as “thermonuclear burst oscillations,” which occur at a frequency of 716 Hz.

These bursts of oscillations match the rotational frequency of the neutron star itself, meaning it is rotating around its axis at a record speed of 716 times per second.

“During the burst, the neutron star becomes up to 100,000 times brighter than the Sun and releases an enormous amount of energy,” said DTU space researcher Dr. Jerome Cheneves.

“We are therefore working on very extreme events, and studying them will provide new insights into the existing life cycles of binary star systems and the formation of elements in the universe.”

of findings will appear in astrophysical journal.

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Gaurava K. Jaisawal others. 2024. A comprehensive study of the 4U 1820-30 thermonuclear X-ray burst by NICER: accretion disk interactions and candidate burst oscillations. APJ 975, 67; doi: 10.3847/1538-4357/ad794e

Source: www.sci.news

IXPE uncovers a new extremely luminous X-ray source in our galaxy

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Cygnus X-3It is an X-ray binary system located about 7,400 parsecs (24,136 light years) away in the constellation Cygnus, and analysis of the data indicates that it is a type of extremely luminous X-ray source. NASA’s Imaging X-ray Polarimetry Probe (IXPE).

The halo around Cygnus X-3. Image courtesy of NASA.

“X-ray binaries are interesting systems that consist of two objects: a normal star and a compact object such as a black hole or neutron star that sucks material from the companion star,” explained astronomer Aleksandra Beredina from the University of Turku and her colleagues.

“To date, several hundred such sources have been identified in our Milky Way galaxy.”

“When it comes to the most powerful phenomena in the Universe, the release of gravitational energy in binary X-ray systems stands out as an extremely efficient process.”

“Among the first X-ray binary systems discovered in the Universe is the Cygnus X-3 system,” the researchers added.

“Since the early 1970s, this binary system has been noted for its ability to briefly appear as one of the most powerful radio sources, only to fade or disappear completely after a few days.”

“This unique feature prompted early efforts to coordinate astronomical observations around the world through telephone coordination.”

“The peculiar behaviour of this system during this short-lived, high-energy event contrasts with its normal nature and led to it being named ‘Astronomical Mystery Cygnus X-3’ by R.M. Helming in 1973.”

“Since then, there have been numerous efforts to understand its properties.”

Dr. Veredina and her co-authors used the Imaging X-ray Polarimetry Explorer to measure the X-ray polarization of Cygnus X-3.

“The X-ray polarization images provide insight into the composition of matter surrounding the compact object in Cygnus X-3,” the researchers said.

“We found that this compact object is surrounded by a dense, opaque membrane of material.”

“The light we see is a reflection from the inner walls of a funnel formed by the surrounding gas, similar to a cup with a mirror on the inside.”

“Cygnus X-3 is a type of Ultraluminous X-ray source (ULX), which consumes material at such a rate that a significant portion of the infalling material does not fall within the event horizon, but rather is ejected out of the system.”

“ULXs are usually observed as points of light in images of distant galaxies, and their radiation is amplified by the focusing effect of the funnel around the compact object, acting like a megaphone,” said Professor Juri Poutanen from the University of Turku.

“But these sources are so far away – thousands of times the extent of the Milky Way – that they appear relatively faint to X-ray telescopes.”

“This discovery reveals that luminous counterparts to these distant ULXs exist within our own Galaxy.”

“This important discovery marks a new chapter in our investigation into the source of this extraordinary universe, providing an opportunity to study its extreme matter consumption in detail.”

of result Published in the journal Natural Astronomy.

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A. Veredina othersIXPE discovered Cygnus X-3 as an ultra-luminous X-ray source in the galaxy. Nat AstronPublished online June 21, 2024, doi: 10.1038/s41550-024-02294-9

Source: www.sci.news