The XMM-Newton Bright Serendipitous Survey
... DSS I/II1 and the SDSS2 ). In particular, we have found the optical counterpart of about 88% of the XBS sources on the DSS with a red magnitude (the APM3 red magnitude) brighter than ∼20.5. All but 6 of the remaining sources have been optically identified either through dedicated photometry or using ...
... DSS I/II1 and the SDSS2 ). In particular, we have found the optical counterpart of about 88% of the XBS sources on the DSS with a red magnitude (the APM3 red magnitude) brighter than ∼20.5. All but 6 of the remaining sources have been optically identified either through dedicated photometry or using ...
Galaxy Assembly through Mergers
... The assembly of new galaxies through mergers of galaxies already in place has been long studied as a path of galaxy formation. Within this hierarchical model, where larger structures are built from smaller ones, more massive galaxies can then be assembled from less massive galaxies, thus contributin ...
... The assembly of new galaxies through mergers of galaxies already in place has been long studied as a path of galaxy formation. Within this hierarchical model, where larger structures are built from smaller ones, more massive galaxies can then be assembled from less massive galaxies, thus contributin ...
Type Ia supernova spectral features in the context of their host
... Kitt Peak National Observatory 4-metre telescope and the Ritchey– Chretien Spectrograph, and the University of Hawaii 88-inch and the Supernova Integral Field Spectrograph (SNIFS; Lantz et al. 2004). All of the spectra used in this paper are available from the WISeREP archive (Yaron & Gal-Yam 2012), ...
... Kitt Peak National Observatory 4-metre telescope and the Ritchey– Chretien Spectrograph, and the University of Hawaii 88-inch and the Supernova Integral Field Spectrograph (SNIFS; Lantz et al. 2004). All of the spectra used in this paper are available from the WISeREP archive (Yaron & Gal-Yam 2012), ...
Supernova - Wikipedia, the free encyclopedia
... System (SNEWS) project has begun using a network of neutrino detectors to give early warning of a supernova in the Milky Way galaxy.[28][29] Neutrinos are particles that are produced in great quantities by a supernova explosion,[30] and they are not significantly absorbed by the interstellar gas and ...
... System (SNEWS) project has begun using a network of neutrino detectors to give early warning of a supernova in the Milky Way galaxy.[28][29] Neutrinos are particles that are produced in great quantities by a supernova explosion,[30] and they are not significantly absorbed by the interstellar gas and ...
Report from the Subaru Telescope for External
... indicates that young galaxies in the distant Universe (at least some of them) emit more ionizing radiation than expected and that they may have played an important role in the cosmic reionization. This is consistent with Ouchi et al. (2009b), which estimated the total ionizing photon budget from the ...
... indicates that young galaxies in the distant Universe (at least some of them) emit more ionizing radiation than expected and that they may have played an important role in the cosmic reionization. This is consistent with Ouchi et al. (2009b), which estimated the total ionizing photon budget from the ...
... ■ Abstract The Universe is in transition. At early times, galactic evolution was dominated by hierarchical clustering and merging, processes that are violent and rapid. In the far future, evolution will mostly be secular—the slow rearrangement of energy and mass that results from interactions involv ...
The VIMOS Ultra-Deep Survey (VUDS): Fast Increase in the Fraction
... Deharveng et al. 2008; Hayes et al. 2014). As a result of their nature, Lyα photons are found to be scattered at much larger scales than UV photons (Steidel et al. 2011; Momose et al. 2014). Predicting the escape fraction of the Lyα photons as a function of the galaxy properties involves including a ...
... Deharveng et al. 2008; Hayes et al. 2014). As a result of their nature, Lyα photons are found to be scattered at much larger scales than UV photons (Steidel et al. 2011; Momose et al. 2014). Predicting the escape fraction of the Lyα photons as a function of the galaxy properties involves including a ...
Hubble 2006: Science Year in Review
... Hubble’s most powerful camera, the Advanced Camera for Surveys (ACS), providing a tenfold improvement over WFPC2. The final servicing mission in 2008 will install two new instruments, the Cosmic Origins Spectrograph (COS) and Wide Field Camera 3 (WFC3). COS is the most sensitive ultraviolet spectrog ...
... Hubble’s most powerful camera, the Advanced Camera for Surveys (ACS), providing a tenfold improvement over WFPC2. The final servicing mission in 2008 will install two new instruments, the Cosmic Origins Spectrograph (COS) and Wide Field Camera 3 (WFC3). COS is the most sensitive ultraviolet spectrog ...
X-Ray Spectroscopy of Stars
... Stars are among the most prominent sources accessible to modern X-ray telescopes. In fact, stars located across almost all regions of a Hertzsprung-Russell diagram have been identified as X-ray sources, with only a few exceptions, most notably A-type stars and the coolest giants of spectral type M. ...
... Stars are among the most prominent sources accessible to modern X-ray telescopes. In fact, stars located across almost all regions of a Hertzsprung-Russell diagram have been identified as X-ray sources, with only a few exceptions, most notably A-type stars and the coolest giants of spectral type M. ...
Galaxy Disks Further
... Disks are the most prominent parts of late-type spiral galaxies. The disk of our own Milky Way Galaxy stretches as a magnificent band of light from horizon to horizon, particularly from a dark site at southern latitudes, as in the Astronomy Picture of the Day for January 27, 2009 (Pacholka 2009). It ...
... Disks are the most prominent parts of late-type spiral galaxies. The disk of our own Milky Way Galaxy stretches as a magnificent band of light from horizon to horizon, particularly from a dark site at southern latitudes, as in the Astronomy Picture of the Day for January 27, 2009 (Pacholka 2009). It ...
W.M. Keck Observatory Annual Report 2009
... II telescope to measure the spectrum of light emitted by each object to determine their composition and distance. The Keck spectra showed that the light from the supernovae traveled nearly 11 billion light years to reach Earth. Prior to this discovery, the astronomical literature showed that the mos ...
... II telescope to measure the spectrum of light emitted by each object to determine their composition and distance. The Keck spectra showed that the light from the supernovae traveled nearly 11 billion light years to reach Earth. Prior to this discovery, the astronomical literature showed that the mos ...
Niraj D. Welikala Thesis - D-Scholarship@Pitt
... The role of star formation in galaxies is clearly a fundamental component of their evolution, although it is becoming clear that galaxy environments may also play a significant role. To explore the relationship between environment and star formation in galaxies, I use the photometric information con ...
... The role of star formation in galaxies is clearly a fundamental component of their evolution, although it is becoming clear that galaxy environments may also play a significant role. To explore the relationship between environment and star formation in galaxies, I use the photometric information con ...
Abstract The Star Formation History of Low Surface Brightness Galaxies
... poorly constrained. These objects tend to be rather blue, contradicting the initial impression that they may simply be faded remnants of higher surface brightness galaxies whose star formation has finished. Other scenarios span a broad range: a young mean age, less dust, a lower metallicity, perhaps ...
... poorly constrained. These objects tend to be rather blue, contradicting the initial impression that they may simply be faded remnants of higher surface brightness galaxies whose star formation has finished. Other scenarios span a broad range: a young mean age, less dust, a lower metallicity, perhaps ...
The Evolution of Star Formation Activity in . Cory R. Wagner
... IRAC Shallow Cluster Survey, and 25 low-redshift (0.15 < z < 1) clusters from The Cluster Lensing And Supernova survey with Hubble. We compare cluster galaxy star formation to that of the field over 0.15 < z < 1.5 using ∼8000 galaxies from the UltraVISTA survey. Mid-infrared star formation rates are ...
... IRAC Shallow Cluster Survey, and 25 low-redshift (0.15 < z < 1) clusters from The Cluster Lensing And Supernova survey with Hubble. We compare cluster galaxy star formation to that of the field over 0.15 < z < 1.5 using ∼8000 galaxies from the UltraVISTA survey. Mid-infrared star formation rates are ...
PDF hosted at the Radboud Repository of the Radboud University
... these elements in type Ia supernova spectra indicate that the progenitors are likely evolved objects that have lost most or all of their hydrogen prior to the explosions. Secondly, latetime light-curves of type Ia supernovae have exponential fall-offs, characteristic of a radioactive decay time simil ...
... these elements in type Ia supernova spectra indicate that the progenitors are likely evolved objects that have lost most or all of their hydrogen prior to the explosions. Secondly, latetime light-curves of type Ia supernovae have exponential fall-offs, characteristic of a radioactive decay time simil ...
Strongly suggested reading: The stellar halo of the Galaxy
... is still evolving significantly. In an attempt to avoid the (almost unavoidable) risk of becoming quickly outdated, the author has decided to review those properties of the stellar halo that (hopefully) provide the most direct clues to its evolutionary path. The stellar halo is arguably the componen ...
... is still evolving significantly. In an attempt to avoid the (almost unavoidable) risk of becoming quickly outdated, the author has decided to review those properties of the stellar halo that (hopefully) provide the most direct clues to its evolutionary path. The stellar halo is arguably the componen ...
Revising the census of low luminosity AGN
... A LOW EW (~1 Å) IS CHARACTERISTIC OF STELLAR PROCESSES AGN 10 - Roma 10/09/2012 ...
... A LOW EW (~1 Å) IS CHARACTERISTIC OF STELLAR PROCESSES AGN 10 - Roma 10/09/2012 ...
High-mass star-forming cloud G0.38+0.04 in the Galactic center dust
... Sgr B2 (M) are also the only H2 CO maser sources with corresponding SiO maser detections and vice versa, though the sample of regions explored in both tracers is small. This high detection rate of masers in star-forming regions within the CMZ, despite limited statistical information, suggests that H ...
... Sgr B2 (M) are also the only H2 CO maser sources with corresponding SiO maser detections and vice versa, though the sample of regions explored in both tracers is small. This high detection rate of masers in star-forming regions within the CMZ, despite limited statistical information, suggests that H ...
Observational Studies of Interacting Galaxies and the Development
... understanding of galaxy merger evolution through both observational studies and instrument developments. Observationally, I approach the goal photometrically and spectroscopically. The photometric studies better constrain the number density evolution of wet and dry mergers through five CFHTLS broad ...
... understanding of galaxy merger evolution through both observational studies and instrument developments. Observationally, I approach the goal photometrically and spectroscopically. The photometric studies better constrain the number density evolution of wet and dry mergers through five CFHTLS broad ...
Type Ia Supernovae
... its expansion, a conclusion that could most easily be explained if more than 70% of the Universe was some previously un-identified form of matter now often referred to as ‘Dark Energy’. Beyond their prominent role as tools to gauge our place in the Universe, supernovae themselves have been studied w ...
... its expansion, a conclusion that could most easily be explained if more than 70% of the Universe was some previously un-identified form of matter now often referred to as ‘Dark Energy’. Beyond their prominent role as tools to gauge our place in the Universe, supernovae themselves have been studied w ...
The visibility of Lyman Alpha Emitters: constraining reionization
... GADGET-2 to obtain the physical properties of z ≃ 5.7 galaxies, (b) a dust model that took into account the entire star formation history of each galaxy to calculate its dust enrichment and, (c) a RT code (CRASH) to obtain the ionization fields to calculate the IGM Lyα transmission for each galaxy, ...
... GADGET-2 to obtain the physical properties of z ≃ 5.7 galaxies, (b) a dust model that took into account the entire star formation history of each galaxy to calculate its dust enrichment and, (c) a RT code (CRASH) to obtain the ionization fields to calculate the IGM Lyα transmission for each galaxy, ...
VIRGO status and GW physics
... The big step forward in the last decade has been the demonstration of the interferometers technology. The design sensitivity has been (almost) reached and stability is so good (unexpectedly) that an efficient network could be created. Virgo, now, has opened the road to very low frequency region. ...
... The big step forward in the last decade has been the demonstration of the interferometers technology. The design sensitivity has been (almost) reached and stability is so good (unexpectedly) that an efficient network could be created. Virgo, now, has opened the road to very low frequency region. ...
The Lake Baikal Three Messenger Conference
... – X-ray Astronomy and Polarimery Presenters: COSTA, Enrico – Implications of the study of galaxy clusters and cosmic large-scale structure on neutrino masses and Dark Matter Presenters: BÖHRINGER, Hans – Decaying dark matter search with NuSTAR deep sky observations Presenters: MALYSHEV, Denys ...
... – X-ray Astronomy and Polarimery Presenters: COSTA, Enrico – Implications of the study of galaxy clusters and cosmic large-scale structure on neutrino masses and Dark Matter Presenters: BÖHRINGER, Hans – Decaying dark matter search with NuSTAR deep sky observations Presenters: MALYSHEV, Denys ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.