A Multi-wavelength study on gamma
... Firstly I’d like to express my gratitude to my Ph.D. supervisor, Dr. Bing Zhang. Bing has influenced me significantly both in research and in daily life. With his enthusiasm, his inspiration, and his great efforts to explain things clearly and simply, he always help make research fun during my study. B ...
... Firstly I’d like to express my gratitude to my Ph.D. supervisor, Dr. Bing Zhang. Bing has influenced me significantly both in research and in daily life. With his enthusiasm, his inspiration, and his great efforts to explain things clearly and simply, he always help make research fun during my study. B ...
Correlation of the highest-energy cosmic rays with the positions of
... about 200 Mpc from earth could contribute significantly to the observed flux above 6 1019 eV. Protons with higher energies interact with cosmic microwave background photons to produce pions [3,4], which leads to a significant attenuation of their flux from more distant sources. The energy of light nuc ...
... about 200 Mpc from earth could contribute significantly to the observed flux above 6 1019 eV. Protons with higher energies interact with cosmic microwave background photons to produce pions [3,4], which leads to a significant attenuation of their flux from more distant sources. The energy of light nuc ...
- IRSA
... help to determine the uniqueness of our planetary system and will greatly improve the estimates of the frequency of other lifebearing planets in the universe. 3) To study ultraluminous galaxies and active galactic nuclei. By measuring the location of the silicate feature, the IRS will be able to me ...
... help to determine the uniqueness of our planetary system and will greatly improve the estimates of the frequency of other lifebearing planets in the universe. 3) To study ultraluminous galaxies and active galactic nuclei. By measuring the location of the silicate feature, the IRS will be able to me ...
X-ray narrow emission lines from the nuclear region of NGC 1365
... Context. NGC 1365 is a Seyfert 2 galaxy with a starburst ring in its nuclear region. In this work we look at the XMM-Newton Reflection Grating Spectrometer (RGS) data from four 2012–13, three 2007 and two 2004 observations of NGC 1365, in order to analyse and characterise in a uniform way the soft X ...
... Context. NGC 1365 is a Seyfert 2 galaxy with a starburst ring in its nuclear region. In this work we look at the XMM-Newton Reflection Grating Spectrometer (RGS) data from four 2012–13, three 2007 and two 2004 observations of NGC 1365, in order to analyse and characterise in a uniform way the soft X ...
Statistics of gamma-ray point sources below the Fermi detection limit
... Faint gamma-ray point sources cannot be detected individually, however their presence affects the statistics of photons across the sky. One can use the observed statistics of photons to infer some general properties about the population of point sources below the Fermi detection limit. The idea of u ...
... Faint gamma-ray point sources cannot be detected individually, however their presence affects the statistics of photons across the sky. One can use the observed statistics of photons to infer some general properties about the population of point sources below the Fermi detection limit. The idea of u ...
EUV and X-ray Spectroscopy of the Active Sun
... flare was then carried out, again utilising observations from a wide range of spacecraft: MESSENGER/SAX, RHESSI, EUVI, Cor1 and Cor2. Observations provided evidence of CME triggering by internal tether-cutting and not by breakout reconnection. A comparison of the confined and eruptive flares suggest ...
... flare was then carried out, again utilising observations from a wide range of spacecraft: MESSENGER/SAX, RHESSI, EUVI, Cor1 and Cor2. Observations provided evidence of CME triggering by internal tether-cutting and not by breakout reconnection. A comparison of the confined and eruptive flares suggest ...
X-ray astronomy of stellar coronae (Review)
... Although often narrowed down to some specific energy ranges, coronal emission is intrinsically a multi-wavelength phenomenon revealing itself from the meter-wave radio range to gamma rays. The most important wavelength regions from which we have learned diagnostically on stellar coronae include the ...
... Although often narrowed down to some specific energy ranges, coronal emission is intrinsically a multi-wavelength phenomenon revealing itself from the meter-wave radio range to gamma rays. The most important wavelength regions from which we have learned diagnostically on stellar coronae include the ...
Introduction to spectroscopic techniques
... Camera not open enough! (luminosity) Conversely, if one wants f/a ~ 3, one needs X = ~ 1 μ ) (remember, pixel was much smaller, ~3μ, in photography!) • Thus will use d > do , i.e. not use full resolution of grating • The exit image is optically conjugated to the entrance slit! Neon school 2006 ...
... Camera not open enough! (luminosity) Conversely, if one wants f/a ~ 3, one needs X = ~ 1 μ ) (remember, pixel was much smaller, ~3μ, in photography!) • Thus will use d > do , i.e. not use full resolution of grating • The exit image is optically conjugated to the entrance slit! Neon school 2006 ...
Section IV High-Energy Astrophysics and Cosmology
... A disk-like geometry of the BLR has been proposed by several authors [4]. Collin et al. [5] suggested that the disk may have a finite half thickness H, or a profile with H increasing more than linearly with the disk radius. Other models propose the existence of warped disks [6]. The authors of [7] a ...
... A disk-like geometry of the BLR has been proposed by several authors [4]. Collin et al. [5] suggested that the disk may have a finite half thickness H, or a profile with H increasing more than linearly with the disk radius. Other models propose the existence of warped disks [6]. The authors of [7] a ...
The effect of helium sedimentation on galaxy cluster masses and
... for light curve filtering to eliminate flares in the background due to solar activity. The exposure times after filtering are given in Table 1. We follow the method described in Bulbul et al. (2010) for background subtraction. We use the 0.7−7.0 keV energy band extraction of spectra and images in or ...
... for light curve filtering to eliminate flares in the background due to solar activity. The exposure times after filtering are given in Table 1. We follow the method described in Bulbul et al. (2010) for background subtraction. We use the 0.7−7.0 keV energy band extraction of spectra and images in or ...
The energy spectrum of cosmic electrons measured with the MAGIC
... Cherenkov telescopes. This is of particular interest as the Cherenkov telescopes observe a cutoff in the electron spectrum just above the energy range measured by the satellites. This thesis presents the final electron spectrum as measured by MAGIC. The electrons are a diffuse flux making the determ ...
... Cherenkov telescopes. This is of particular interest as the Cherenkov telescopes observe a cutoff in the electron spectrum just above the energy range measured by the satellites. This thesis presents the final electron spectrum as measured by MAGIC. The electrons are a diffuse flux making the determ ...
VLT observations of GRS 1915+ 105
... Since the discovery of superluminal episodes in GRS 1915+105, this object has been under strong surveillance by several observers at different wavelengths. In spite of this work, the nature of the X-ray binary system in GRS 1915+105 is still a matter of debate. The strong interstellar absorption tow ...
... Since the discovery of superluminal episodes in GRS 1915+105, this object has been under strong surveillance by several observers at different wavelengths. In spite of this work, the nature of the X-ray binary system in GRS 1915+105 is still a matter of debate. The strong interstellar absorption tow ...
Observation of the Crab pulsar wind nebula and microquasar Ph.D. Dissertation
... Energy (VHE) band. The last generation of IACTs, with the High Energy Stereoscopic System (HESS), Very Energetic Radiation Imaging Telescope Array System (VERITAS), and Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes, have been capable to increase the total number of known VHE emitt ...
... Energy (VHE) band. The last generation of IACTs, with the High Energy Stereoscopic System (HESS), Very Energetic Radiation Imaging Telescope Array System (VERITAS), and Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes, have been capable to increase the total number of known VHE emitt ...
Astroparticle Physics: γ-Rays
... n Introduction! n Detectors and Detection techniques! n Origin of γ–rays in Astrophysical sources! – Basic production processes ! – Acceleration mechanisms! ...
... n Introduction! n Detectors and Detection techniques! n Origin of γ–rays in Astrophysical sources! – Basic production processes ! – Acceleration mechanisms! ...
Functional and Performance Requirements
... FUNCTIONAL AND PERFORMANCE REQUIREMENTS DOCUMENT Andrew Sheinis ...
... FUNCTIONAL AND PERFORMANCE REQUIREMENTS DOCUMENT Andrew Sheinis ...
the redshift evolution of the mean temperature
... photon counts at r > 0.2R500 (see Figure 1), and exclude four clusters with exceptionally high signal-to-noise (SPT-CLJ06585556 (the Bullet Cluster), SPT-CLJ2248-4431, SPT-CLJ02324421, SPT-CLJ0102-4915), which could dominate the stacking analysis, and one cluster with very low counts (SPT-CLJ0037504 ...
... photon counts at r > 0.2R500 (see Figure 1), and exclude four clusters with exceptionally high signal-to-noise (SPT-CLJ06585556 (the Bullet Cluster), SPT-CLJ2248-4431, SPT-CLJ02324421, SPT-CLJ0102-4915), which could dominate the stacking analysis, and one cluster with very low counts (SPT-CLJ0037504 ...
A stacking method to study the gamma
... Depending on the ROI size, the number of detected point sources increases rapidly and leads for the co-adding to a model with a large number of components. In order to keep the model simply structured, we follow a different strategy. Before coadding the data, a binned likelihood analysis6 is performe ...
... Depending on the ROI size, the number of detected point sources increases rapidly and leads for the co-adding to a model with a large number of components. In order to keep the model simply structured, we follow a different strategy. Before coadding the data, a binned likelihood analysis6 is performe ...
L31 ON THE DISAPPEARANCE OF KILOHERTZ QUASI
... One critical question is whether the neutron star magnetosphere can be disengaged from the Keplerian disk at the last stable orbit. Studies have shown that the evolution of the magnetic field configuration is very complicated as the disk approaches the last stable orbit (e.g., Lai 1998), but the exa ...
... One critical question is whether the neutron star magnetosphere can be disengaged from the Keplerian disk at the last stable orbit. Studies have shown that the evolution of the magnetic field configuration is very complicated as the disk approaches the last stable orbit (e.g., Lai 1998), but the exa ...
The Physics of Background Discrimination in Liquid Xenon, and First Results from Xenon10 in the Hunt for WIMP Dark Matter
... We also build a simple recombination model that successfully reproduces the mean recombination in electron and nuclear recoils, including the the surprising reversal of the expected trend for recombination with ionization density in low energy electron recoils. The model also reproduces the measured ...
... We also build a simple recombination model that successfully reproduces the mean recombination in electron and nuclear recoils, including the the surprising reversal of the expected trend for recombination with ionization density in low energy electron recoils. The model also reproduces the measured ...
UvA-DARE (Digital Academic Repository) Multi
... the first optical afterglow (Van Paradijs et al. 1997). This breakthrough was followed a few months later when the afterglow of GRB 970508 was also detected at the other end of the electromagnetic spectrum, in radio (Frail et al. 1997). The sub-arcsecond positions of X-ray and optical identification ...
... the first optical afterglow (Van Paradijs et al. 1997). This breakthrough was followed a few months later when the afterglow of GRB 970508 was also detected at the other end of the electromagnetic spectrum, in radio (Frail et al. 1997). The sub-arcsecond positions of X-ray and optical identification ...
OLIMPO
... The strength of the effect does not depend on the distance of the Cluster ! So it is possible to see very distant clusters (not visible in optical/X). ...
... The strength of the effect does not depend on the distance of the Cluster ! So it is possible to see very distant clusters (not visible in optical/X). ...
ON THE RADIAL ONSET OF CLUMPING IN THE WIND OF... J. M. Torrejón , N. S. Schulz , M. A. Nowak
... fraction6 of ∼54%. In order to minimize the modulation effect due to the NS spin in Figure 1 we have binned the whole light curve into 526 s bins. The observed light curves S and H show significant variability from bin to bin and and along the whole observation. This is quite common among HMXBs with ...
... fraction6 of ∼54%. In order to minimize the modulation effect due to the NS spin in Figure 1 we have binned the whole light curve into 526 s bins. The observed light curves S and H show significant variability from bin to bin and and along the whole observation. This is quite common among HMXBs with ...
Light and Telescopes Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015
... LA Mission College Spring F2015 ...
... LA Mission College Spring F2015 ...
The Propagation of Ultra High Energy Cosmic Rays
... The total number of particular species (A) arriving at Earth from a uniform distribution of Iron nuclei sources with particles at each source injected according to an energy spectral index α . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
... The total number of particular species (A) arriving at Earth from a uniform distribution of Iron nuclei sources with particles at each source injected according to an energy spectral index α . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
The Early-time Optical Properties of Gamma
... It was clear that rapid response to obtain early-time optical observations with ground based robotic telescopes was required to pin down the open issue of the emission mechanism for the GRB itself and its afterglow. However, the small number of prompt optical observations simultaneous to the GRB γ-r ...
... It was clear that rapid response to obtain early-time optical observations with ground based robotic telescopes was required to pin down the open issue of the emission mechanism for the GRB itself and its afterglow. However, the small number of prompt optical observations simultaneous to the GRB γ-r ...
X-ray astronomy detector
X-ray astronomy detectors are instruments that detect X-rays for use in the study of X-ray astronomy.X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray emission from celestial objects. X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites. X-ray astronomy is part of space science.X-ray astronomy detectors have been designed and configured primarily for energy and occasionally for wavelength detection using a variety of techniques usually limited to the technology of the time.