A kilo nucleus is following a burst of high-energy radiation

The first two binary neutron star mergers: GW170817 vs GRB 170817A, and implications for astrophysics

Abbott, B. P. et al. Gravitational waves and gamma-rays from a binary neutron star merger: GW170817 and GRB 170817A. Astrophys. J. Lett. 848, L13 (2017).

Blanchard, P. K. et al. The merger of LIGO andVirgo was an example of a magnetically analogous event. VII. Properties of the host galaxy and constraints on the merger timescale. There are astrophys. A person named J. 848, L22.

Arcavi, I. The importance of early optical and ultraviolet observations for constraining emission models is mentioned in the first hours of the GW170817 kilonova. Astrophys. J. 855, 23 (2018).

Alexander, K. D. A decline in the X-Ray through radio emission from GW170817 continues to support an off-axis structured jet. Astrophys. J. Lett. 863, L18 (2018).

Bellini, A., Anderson, J., and Bedin are part of the team that does photometry with HST WFC3. I. There were geometric-distortion changes to the UVIS channel. Publ. Astron. Soc. Pac. 123, 622 (2011).

Greisen, E. W. in Information Handling in Astronomy—Historical Vistas Astrophysics and Space Science Library Vol. 285 (ed. Heck, A.) 109–125 (Springer, 2003).

Pradel, N., Charlot, P. & Lestrade, J.-F. Astrometric accuracy of phase-referenced observations with the VLBA and EVN. Astron. 452,10997-1106 are related totrophys.

Kovalev, Y. Y., Petrov, L. & Plavin, A. V. VLBI-Gaia offsets favor parsec-scale jet direction in active galactic nuclei. Astron. Astrophys. 598, L1 (2017).

Plavin, A. V., and Kovalev, Y. Y., were present. There are differences in the positions and proper motions of Gaia DR2 that need to be analyzed. Mon. Not. R. Astron. Soc. 482, 3023–3031 (2019).

Charlot, P. et al. The third realization of the International Celestial Reference Frame by very long baseline interferometry. Astron. Astrophys. 594, A158 ( 2020.

Bloom, J. S., Kulkarni, S. R. & Djorgovski, S. G. The nature of the progenitors is shown in the observed offset distribution of gamma-ray bursts from their host galaxies. Astron. J. 123, 1111–1148 (2002).

Speagle, J. S. DYNESTY: a dynamic nested sampling package for estimating Bayesian posteriors and evidences. Mon. Not. R. Astron. In 2020 the Soc. 493 and 3132–3158 were published.

Dark Energy Survey and the Fermi GRB Team. I. GRB 211211A and GRB IKI FuN. Photometry and Spectroscopy

The Dark Energy Survey and the Dark Energy Camera are included in the book. The same thing as the quark star merger LIGO/Virgo. The discovery was made using the dark energy camera. Astrophys. J. 832, L16

Dunwoody, R., and Meegan, C., are members of the Fermi GBM Team. The GRB is called GRB 211211A. Fermi GBM observation. The GRB Coordinates Network has a circular service.

Nicholl, M. et al. Tight multimessenger constraints on the neutron star equation of state from GW170817 and a forward model for kilonova light-curve synthesis. Mon. Not. R. Astron. Soc. 505, 3016–3032 (2021).

Dust heating as an alternative to a kilonova following the long duration of GRB 2110 is shown by strong NIR emission. You can preprint at thearxiv.org.

The effects of r-process heating on accretion in compact objects. Mon. Not. R. Astron. Soc. 402, 2728 and 281 (2010).

Adriani, O. et al. Extended measurement of the cosmic-ray electron and positron spectrum from 11 GeV to 4.8 TeV with the calorimetric electron telescope on the International Space Station. Lett. 120, 261101.

The GRB IKI FuN. has a redshift estimation and a correlation detection. The GRB has a circular service.

T. et al. Photometry and spectroscopy of GRB 030329 and its associated supernova 2003dh: the first two months. There are astrophys. J. 599, 394–407 (2003).

Hook, I. M. et al. The Gemini–North Multi-Object Spectrograph has a number of modes that it performs in. There is a publ. Astron. Soc. Pac. 116, 425–440 (2004).

Labrie, K., Anderson, K., Cárdenes, R., Simpson, C. & Turner, J. E. H. DRAGONS – Data Reduction for Astronomy from Gemini Observatory North and South. ASP Conf. Ser. 523, 321.

Lang, D., Hogg, D. W., Mierle, K., Blanton, M. & Roweis, S. Astrometry.net: blind astrometric calibration of arbitrary astronomical images. Astron. J. 139, 1782–1 800 was published in 2010.

The reddening and recalibrating of the SFD was measured with the Sloan Digital Sky Survey. Astrophys. J. 737, 103 (2011).

Willmer, C N. A. and others. The Deep Evolutionary Exploratory Probe 2 galaxy redshift survey: the galaxy luminosity function to z ~ 1. trophys. J. 647, 853–873 (2006).

Finkelstein, S. L. et al. The ultraviolet function of the galaxy is growing over the course of two billion years. Astrophys. J. 800, 71.

Nugent, A. E. et al. The distant, galaxy cluster environment of the short GRB 161104A at z ~ 0.8 and a comparison to the short GRB host population. There are astrophys. J. 904, 52 (2020).

E. L. Wright wrote about the topic. The Wide-field Infrared Survey Explorer (WISE) has two things in common. We are astron. J. 140 was published in 1868.

There is propagation of uncertainties in stellar population synthesis modeling. I. Uncertain aspects of stellar evolution and the initial mass function are relevant to the derived physical properties of a galaxies. There are astrophys. J. 699, 486–506 (2009).

Lamb, G. P. & Kobayashi, S. Electromagnetic counterparts to structured jets from gravitational wave detected mergers. Mon. Not. R. Astron. 472 and 499 were written in the same year.

A pair of star mergers were inferred using multimessenger parameters. There was a public event on Mon. Not. R. Astron. This week: Soc. 487, 91-95.

On August 17, 2017, astrophysicists witnessed two dead stars’ remnant cores, known as neutron stars, colliding into each other in a distant galaxy. The event was detected through ripples in spacetime and light that came from the explosion. This marked the first and only time scientists had seen such an event using gravitational waves. From those signals, they deduced that the neutron stars were 1.1 to 1.6 times the mass of the Sun. They also figured out that such collisions create some of the heavier natural elements found in the universe, such as gold and platinum. The signals presented more puzzles than answers.

S. Khan, et al. Frequency-domain gravitational waves from nonprecessing black-hole binaries. II. The advanced detector era model is a phenomenological one. Phys. Rev. D 93, 044007 (2016).

From high-resolution numerical relativity simulations, closed-form tidal approximants were built for a sample of two neutron star gravitational waves. Phys. Rev. D 96, 121501 (2017).

O’Connor, B. et al. There are constraints on detection of kilonova in two short GRBs. Mon. Not. R. Astron. Soc. 502, 1279–1298 (2021).

Moskvitin, A., Spiridonova, O., Belkin, S., Pozanenko, A. & Pankov, N.; GRB IKI FuN. GRB 211211A: SAO RAS optical observations. GRB Coordinates Network, Circular Service, No. 31234 (2021).

The first confirmed detection of a star system that could produce a kilonova, when stars collide and release heavy elements into space, is a part of this system. The rare stellar pair is believed to be one of only about 10 like it in the Milky Way galaxy.

In 2016 NASA detected a large flash of X-ray light from a hot, bright Be-type star that was located in the same region.

Astronomers were curious if the two could potentially be linked, so data was captured using the Cerro Tololo Inter-American Observatory’s 1.5-meter telescope in northern Chile.

Dr. Noel D. Richardson was interested in using the data to learn more about the star.

Clarissa Pavao approached Richardson after taking his astronomy class to see if he could work on any projects she might be interested in. He taught Pavao how to clean the telescope data from the telescope in Santiago in order to reduce distortion.

Be stars tend to have disks of matter around them but the telescope looks at a star and it takes in all the light so that you can see elements that make up this star. “It’s hard to see directly through all that stuff.”

An Ultra-stripped Supernova Produced a Dense Pair of Stellar Pairs. I. The Case for a Depleted Secondary Star

She sent her initial results — which resembled something like a scatterplot — to Richardson, who recognized that she had pinned down an orbit for the double-star system. The follow up observations helped verify the star system’s location.

There were two stars, a larger one and a small one, in a very close circle. Richardson said that the smaller star, which grew from 8 or 9 times the mass of our sun to 18 or 19 times the mass of our sun, was created by the larger star’s release of hydrogen. For comparison’s sake, our sun’s mass is 333,000 times that of Earth.

The main star became smaller and smaller while building up the secondary star — and by the time it had exhausted all of its fuel, there wasn’t enough to create a massive, energetic supernova to release its remaining material into space.

“The star was so depleted that the explosion didn’t even have enough energy to kick (its) orbit into the more typical elliptical shape seen in similar binaries,” Richardson said.

A dense remnant from the ultra-stripped supernova is currently traveling around a rapidly rotating massive star. The stellar pair will stay in the same configuration for about 6 to 7 million years. Because both mass and angular momentum were transferred to the Be star, it releases a disk of gas to maintain balance and make sure it doesn’t rip itself apart.

The secondary star will burn through its fuel to expand and release material that the first star did. But that material can’t be easily piled up on the neutron star, so instead, the star system will release the material through space. The secondary star will likely turn into a neutron star after a lackluster supernova.

Source: https://www.cnn.com/2023/02/01/world/supernova-rare-star-pair-scn/index.html

The Birth and Death of the Universe, with Applications to Astronomy and Space Physicists: Stellar Genealogy and the Interaction Between Two Early-Type Stars

“Those heavy elements allow us to live the way that we do. For example, most gold was created by stars similar to the supernova relic or neutron star in the binary system that we studied. Astronomy deepens our understanding of the world and our place in it,” Richardson said.

“When we look at these objects, we’re looking backward through time,” Pavao said. We get to learn more about the origins of the universe, which will help us figure out where our solar system is headed. Humans used the same elements as these stars.

Richardson and Pavao also worked with physicist Jan J. Eldridge at the University of Auckland in New Zealand, an expert on binary star systems and their evolution. The study looked at 10 star models and estimated that there was just one similar model in the whole Milky Way.

Next, the researchers want to work on learning more about the Be star itself, and hope to conduct follow-up observations using the Hubble Space Telescope. Pavao is also setting her sights on graduating — and continuing to work on space physics research using the new skills she has acquired.

Forget archaeologists and their lost civilizations, or paleontologists with their fossils—astrophysicist Heloise Stevance studies the past on an entirely different scale. When astronomers catch a glimpse of an unusual signal in the sky, perhaps the light from a star exploding, Stevance takes that signal and rewinds the clock on it by billions of years. Working at the University of Auckland in New Zealand, she traces the past lives of dead and dying stars, a process she calls stellar genealogy. She said there was a lot of drama in the lives of stars.

Researchers don’t know how common these mergers are, and they can’t tell if they created all the heavy elements or just a fraction. astrophysicists can answer deeper questions, like how old the universe is, if more of these mergers are observed. This is where stellar genealogy can help.

The work also describes interactions between the two stars before they burned out their fuel to become neutron stars. They started tens of millions of kilometers apart, which sounds far but is actually well under the distance between Earth and the Sun. A stellar envelope surrounds the exteriors of each star. The models of Stevance and her team show that over the stars lifetimes, one star’s envelope engulfed the other and their gases merged to become a single shared envelope.