Gao 2009 用晚期的内激波解释 GRB 080129 的光学耀发

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Title:		Optical/infrared flares of GRB 080129 from late internal shocks
Authors:		Gao, Wei-Hong
Publication:		eprint arXiv:0903.2768
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - Solar and Stellar Astrophysics
Comment:		12 pages, 3 figures, 1 table, accepted for publication in ApJ
Bibliographic Code:		2009arXiv0903.2768G

Abstract

Strong optical and near-infrared (NIR) flares were discovered in the afterglow of GRB 080129. Their temporal behaviors, the sudden emergence and the quick disappearance, are rather similar to that of many X-ray flares (for instance, the giant flare of GRB 050502B). We argue that the optical/NIR flares following GRB 080129 are a low energy analogy of the X-ray flares and the most likely interpretation is the "late internal shock model". In this model, both the very sharp decline and the very small ratio between the duration and the occurrence time of the optical/NIR flares in GRB 080129 can be naturally interpreted. The initial Lorentz factor of the flare outflow is found to be $\sim 30$, consistent with the constraint $\leq 120$ set by the forward shock afterglow modeling. Other possibilities, like the reverse shock emission or the radiation from the continued but weaker and weaker collision between the initial GRB outflow material, are disfavored.

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Bagoly 2004 通过暴本身估算红移

主要内容:
类似光学的photometric方法

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Title:		Redshifts of the Long Gamma-Ray Bursts
Authors:		Bagoly, Z.; Csabai, I.; Meszaros, A.; Meszaros, P.; Horvath, I.; Balazs, L. G.; Vavrek, R.
Publication:		eprint arXiv:0704.0864
Publication Date:		04/2007
Origin:		ARXIV
Keywords:		Astrophysics
Comment:		published in Baltic Astronomy; Baltic Astron. 13 (2004) 227
Bibliographic Code:		2007arXiv0704.0864B

Abstract

The low energy spectra of some gamma-ray bursts' show excess components beside the power-law dependence. The consequences of such a feature allows to estimate the gamma photometric redshift of the long gamma-ray bursts in the BATSE Catalog. There is good correlation between the measured optical and the estimated gamma photometric redshifts. The estimated redshift values for the long bright gamma-ray bursts are up to z=4, while for the the faint long bursts - which should be up to z=20 - the redshifts cannot be determined unambiguously with this method. The redshift distribution of all the gamma-ray bursts with known optical redshift agrees quite well with the BATSE based gamma photometric redshift distribution.

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Frail 2003 1997-2001对伽玛暴射电余辉观测的总结

主要内容:
一共75个余辉的观测

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对不同波段的观测的观测数目的统计(但总数是55),


对每个暴观测次数的统计

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Title:		A Complete Catalog of Radio Afterglows: The First Five Years
Authors:		Frail, D. A.; Kulkarni, S. R.; Berger, E.; Wieringa, M. H.
Affiliation:		AA(National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801.; Division of Physics, Mathematics, and Astronomy, MS 105-24, California Institute of Technology, Pasadena, CA 91125.), AB(Division of Physics, Mathematics, and Astronomy, MS 105-24, California Institute of Technology, Pasadena, CA 91125.), AC(Division of Physics, Mathematics, and Astronomy, MS 105-24, California Institute of Technology, Pasadena, CA 91125.), AD(Australia Telescope National Facility, CSIRO, P.O. Box 76, Epping NSW 1710, Australia.)
Publication:		The Astronomical Journal, Volume 125, Issue 5, pp. 2299-2306. (AJ Homepage)
Publication Date:		05/2003
Origin:		UCP
AJ Keywords:		Cosmology: Observations, Gamma Rays, Radio Continuum
Abstract Copyright:		(c) 2003: The American Astronomical Society
DOI:		10.1086/374364
Bibliographic Code:		2003AJ....125.2299F

Abstract

We present a catalog of 75 gamma-ray bursts (GRBs) that occurred between 1997 and 2001 and for which accurate positions were obtained by the BeppoSAX satellite, the Interplanetary Network, the Rossi X-Ray Timing Experiment satellite, and the High Energy Transient Experiment satellite. As a result of these localizations, we carried out sensitive searches for radio afterglows using the Very Large Array and the Australia Telescope Compact Array, at a frequency of 5 or 8.5 GHz. Subsequent afterglow detections were followed up using several facilities at centimeter, millimeter, and submillimeter wavelengths. The final catalog has 25 afterglow detections and consists of 1521 flux density measurements (or upper limits) at frequencies between 1.4 and 650 GHz. We argue that our search strategy is capable of identifying radio afterglows and distinguishing them from other extragalactic variables whose areal density we derive to be <~1.6×10^-3 arcmin^-2. In addition to complete radio light curves for all cosmological GRBs, the catalog also contains the entire data set for SN 1998bw, an unusual Type Ib/c supernova coincident with GRB 980425.

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Wang 2009 GRB 080916C的辐射机制

主要内容:
单一同步辐射解释的最好.

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Title:		GRB 080916C: on the radiation origin of the prompt emission from KeV/MeV to GeV
Authors:		Wang, Xiang-Yu; Li, Zhuo; Dai, Zi-Gao; Meszaros, Peter
Publication:		eprint arXiv:0903.2086
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - High Energy Astrophysical Phenomena
Comment:		5 pages (emulateapj), no figures, submitted to ApJ Letters
Bibliographic Code:		2009arXiv0903.2086W

Abstract

Fermi observations of high-energy gamma-ray emission from GRB 080916C shows that its spectrum is consistent with the Band function from MeV to tens of GeV. Assuming one single emission mechanism dominates in the whole energy range, we show that this spectrum is consistent with synchrotron origin by shock-accelerated electrons. The simple electron inverse-Compton model and the hadronic model are found to be less viable. In the synchrotron scenario, the synchrotron self-Compton scattering is likely to be in the Klein-Nishina regime and therefore the resulting high-energy emission is subdominant, even though the magnetic field energy density is lower than that in relativistic electrons. The Klein-Nishina inverse-Compton cooling may also affect the low-energy electron number distribution and hence results in a low-energy synchrotron photon spectrum $n \nu^{-1}$ below the peak energy. Under the framework of the electron synchrotron interpretation, we constrain the shock microphysical parameters and derive a lower limit of the upstream magnetic fields. The detection of synchrotron emission extending to about 70 GeV in the source frame in GRB 080916C favors the Bohm diffusive shock acceleration if the bulk Lorentz factor of the relativistic outflow is not significantly greater than thousands.

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Branchini 2009 用伽玛暴研究WHIM(温热星际介质)

主要内容:
通过谱线
算是路上环境

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Title:		Studying the WHIM with Gamma Ray Bursts
Authors:		Branchini, E.; Ursino, E.; Corsi, A.; Martizzi, D.; Amati, L.; den Herder, J. W.; Galeazzi, M.; Gendre, B.; Kaastra, J.; Moscardini, L.; Nicastro, F.; Ohashi, T.; Paerels, F.; Piro, L.; Roncarelli, M.; Takei, Y.; Viel, M.
Publication:		eprint arXiv:0903.1861
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - Cosmology and Extragalactic Astrophysics
Comment:		16 pages, 16 figures, accepted for publication by ApJ
Bibliographic Code:		2009arXiv0903.1861B

Abstract

We assess the possibility to detect and characterize the physical state of the missing baryons at low redshift by analyzing the X-ray absorption spectra of the Gamma Ray Burst [GRB] afterglows, measured by a micro calorimeters-based detector with 3 eV resolution and 1000 cm2 effective area and capable of fast re-pointing, similar to that on board of the recently proposed X-ray satellites EDGE and XENIA. For this purpose we have analyzed mock absorption spectra extracted from different hydrodynamical simulations used to model the properties of the Warm Hot Intergalactic Medium [WHIM]. These models predict the correct abundance of OVI absorption lines observed in UV and satisfy current X-ray constraints. According to these models space missions like EDGE and XENIA should be able to detect about 60 WHIM absorbers per year through the OVII line. About 45 % of these have at least two more detectable lines in addition to OVII that can be used to determine the density and the temperature of the gas. Systematic errors in the estimates of the gas density and temperature can be corrected for in a robust, largely model-independent fashion. The analysis of the GRB absorption spectra collected in three years would also allow to measure the cosmic mass density of the WHIM with about 15 % accuracy, although this estimate depends on the WHIM model. Our results suggest that GRBs represent a valid, if not preferable, alternative to Active Galactic Nuclei to study the WHIM in absorption. The analysis of the absorption spectra nicely complements the study of the WHIM in emission that the spectrometer proposed for EDGE and XENIA would be able to carry out thanks to its high sensitivity and large field of view.

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2009 Greiner 测偏振和光谱的GRIPS计划

主要内容:
卫星计划, 想测z>13的暴
Gamma-ray burst investigation via polarimetry and spectroscopy (GRIPS)

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Title:		Gamma-ray burst investigation via polarimetry and spectroscopy (GRIPS)
Authors:		Greiner, J.; Iyudin, A.; Kanbach, G.; Zoglauer, A.; Diehl, R.; Ryde, F.; Hartmann, D.; Kienlin, A. V.; McBreen, S.; Ajello, M.; Bagoly, Z.; Balasz, L. G.; Barbiellini, G.; Bellazini, R.; Bezrukov, L.; Bisikalo, D. V.; Bisnovaty-Kogan, G.; Boggs, S.; Bykov, A.; Cherepashuk, A. M.; Chernenko, A.; Collmar, W.; Dicocco, G.; Dröge, W.; Gierlik, M.; Hanlon, L.; Horvath, I.; Hudec, R.; Kiener, J.; Labanti, C.; Langer, N.; Larsson, S.; Lichti, G.; Lipunov, V. M.; Lubsandorgiev, B. K.; Majczyna, A.; Mannheim, K.; Marcinkowski, R.; Marisaldi, M.; McBreen, B.; Meszaros, A.; Orlando, E.; Panasyuk, M. I.; Pearce, M.; Pian, E.; Poleschuk, R. V.; Pollo, A.; Pozanenko, A.; Savaglio, S.; Shustov, B.; Strong, A.; Svertilov, S.; Tatischeff, V.; Uvarov, J.; Varshalovich, D. A.; Wunderer, C. B.; Wrochna, G.; Zabrodskij, A. G.; Zeleny, L. M.
Affiliation:		AA(Max-Planck-Institut für extraterrestrische Physik), AB(), AC(), AD(), AE(), AF(), AG(), AH(), AI(), AJ(), AK(), AL(), AM(), AN(), AO(), AP(), AQ(), AR(), AS(), AT(), AU(), AV(), AW(), AX(), AY(), AZ(), BA(), BB(), BC(), BD(), BE(), BF(), BG(), BH(), BI(), BJ(), BK(), BL(), BM(), BN(), BO(), BP(), BQ(), BR(), BS(), BT(), BU(), BV(), BW(), BX(), BY(), BZ(), CA(), CB(), CC(), CD(), CE(), CF(), CG()
Publication:		Experimental Astronomy, Volume 23, Issue 1, pp.91-120 (ExA Homepage)
Publication Date:		03/2009
Origin:		SPRINGER
Abstract Copyright:		(c) 2009: The Author(s)
DOI:		10.1007/s10686-008-9102-0
Bibliographic Code:		2009ExA....23...91G

Abstract

The primary scientific goal of the GRIPS mission is to revolutionize our understanding of the early universe using γ-ray bursts. We propose a new generation gamma-ray observatory capable of unprecedented spectroscopy over a wide range of γ-ray energies (200 keV–50 MeV) and of polarimetry (200–1000 keV). The γ-ray sensitivity to nuclear absorption features enables the measurement of column densities as high as 10²⁸cm ^{‑ 2}. Secondary goals achievable by this mission include direct measurements of all types of supernova interiors through γ-rays from radioactive decays, nuclear astrophysics with massive stars and novae, and studies of particle acceleration near compact stars, interstellar shocks, and clusters of galaxies.

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Gotz 2009 GRB 041219A的偏振观测

主要内容:
偏振度: 43+/-25%

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Title:		Variable polarization measured in the prompt emission of GRB 041219A using IBIS on board INTEGRAL
Authors:		Gotz, D.; Laurent, P.; Lebrun, F.; Daigne, F.; Bosnjak, Z.
Publication:		eprint arXiv:0903.1712
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Comment:		7 pages, 3 figures, accepted for publication in the Astrophysical Journal Letters
Bibliographic Code:		2009arXiv0903.1712G

Abstract

Polarization measurements provide direct insight into the nature of astrophysical processes. Unfortunately, only a few instruments are available for this kind of measurements at gamma-ray energies, and the sources need to be very bright. Gamma-Ray Bursts (GRBs) are ideal candidates due to their large flux over limited time intervals, maximizing the available signal-to-noise ratio. To date a few polarization measurements have been reported, claiming of a high degree of polarization in the prompt emission of GRBs but with low statistical evidence. We used the IBIS telescope on board the INTEGRAL satellite to measure the polarization of the prompt gamma-ray emission of the long and bright GRB 041219A in the 200-800 keV energy band. We find a variable degree of polarization ranging from less than 4% over the first peak to 43+/-25% for the whole second peak. Time resolved analysis of both peaks indicates a high degree of polarization, and the null average polarization in the first peak can be explained by the rapid variations observed in the polarization angle and degree. Our results are consistent with different models for the prompt emission of GRBs at these energies, but they favor synchrotron radiation from a relativistic outflow with a magnetic field which is coherent on an angular size comparable with the angular size of the emitting region (~1/Gamma) . Indeed this model has the best capabilities to maintain a high polarization level, and to produce the observed variability.

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Melandri 2009 GRB 070419A的X-ray和光学余辉

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余辉的光变

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Title:		Evidence for energy injection and a fine-tuned central engine at optical wavelengths in GRB 070419A
Authors:		Melandri, A.; Guidorzi, C.; Kobayashi, S.; Bersier, D.; Mundell, C. G.; Milne, P.; Pozanenko, A.; Li, W.; Filippenko, A. V.; Urata, Y.; Ibrahimov, M.; Steele, I. A.; Gomboc, A.; Smith, R. J.; Tanvir, N. R.; Rol, E.
Publication:		eprint arXiv:0903.1414
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Extragalactic Astrophysics
Comment:		9 pages, 10 figures, accepted for publication in MNRAS
Bibliographic Code:		2009arXiv0903.1414M

Abstract

We present a comprehensive multiwavelength temporal and spectral analysis of the FRED GRB 070419A. The early-time emission in the $\gamma$-ray and X-ray bands can be explained by a central engine active for at least 250 s, while at late times the X-ray light curve displays a simple power-law decay. In contrast, the observed behaviour in the optical band is complex (from 10$^2$ up to 10$^6$ s). We investigate the light curve behaviour in the context of the standard forward/reverse shock model; associating the peak in the optical light curve at $\sim$450 s with the fireball deceleration time results in a Lorenz factor $\Gamma \approx 350$ at this time. In contrast, the shallow optical decay between 450 and 1500 s remains problematic, requiring a reverse shock component whose typical frequency is above the optical band at the optical peak time for it to be explained within the standard model. This predicts an increasing flux density for the forward shock component until t $\sim$ 4 $\times$ 10$^6$ s, inconsistent with the observed decay of the optical emission from t $\sim$ 10$^4$ s. A highly magnetized fireball is also ruled out due to unrealistic microphysic parameters and predicted light curve behaviour that is not observed. We conclude that a long-lived central engine with a finely tuned energy injection rate and a sudden cessation of the injection is required to create the observed light curves - consistent with the same conditions that are invoked to explain the plateau phase of canonical X-ray light curves of GRBs.

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关于高能粒子探测器

既然我们只要知道高能粒子的能量和时间, 那么是不是用一个简单的测力器就可以了. 只不过这个东东要非常灵敏.

基本想法是弄一块板子, 下面安个测力器. 当来一个粒子撞到板子上, 测力器记下强度, 加上时间. 差不多就可以了.

首先来看看可行性:
假设要探测一颗1GeV的光子, 它的冲量是:
1GeV*1.6E-12erg/GeV*1e-7J/erg/(3e8m/s) ~ 5e-28 J*s/m
假设仪器的反应时间是1\mu s, 用 F t=P, 得相当于受力为
F ~ 5e-28 J*s/m / 1e-6 s ~ 5e-23 J/m ~ 5e-23N.

目前最灵敏的称(http://www.fssti.gov.cn/kjj/kjdt/dtw337.htm)可以称出1e-21克, 相当于 1e-21 g * 10^-3 kg/g * 10 N/kg ~ 1e-23 N.
基本上, 勉强可以用来测1GeV的粒子了. 不过如果是TeV的就更容易测一点啦.


再看看具体一点的:
要能拦截这个光子, 板子得比较密比较厚, 这可能要求东西比较重.

但是如果太重的话, 对一个粒子的冲量相应可能很小, 这可以通过弄多个柱子, 每个柱子的质量就相对小一些了.

还要探测方向, 于是不只在柱子底部放称, 侧面也放称, 通过底部和侧面的力的大小比较得到方向.



不过貌似不能分辨是光子还是其他粒子. 但这个估计是可以解决的, 比如不同的东东光深不同(或者叫和材料的作用截面不同).

验证广义相对论的GPB卫星, 要放一个完全走测地线的陀螺, 就用到了激光定位的. 我估计这里也可以用的上这个.

Grupe 2009 GRB 060729的晚期X射线余辉

主要内容:
主要是Chandra的观测

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光变
多个光变的比较

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Title:		Late-time detections of the X-ray afterglow of GRB 060729 with Chandra - the latest detections ever of an X-ray afterglow
Authors:		Grupe, Dirk; Burrows, David N.; Xue-Feng; Wang, Xiang-Yu; Zhang, Bing; Garmire, Gordon; Nousek, John A.; Gehrels, Neil; Ricker, George; Bautz, Marshall W.
Publication:		eprint arXiv:0903.1258
Publication Date:		03/2009
Origin:		ARXIV
Keywords:		Astrophysics - Cosmology and Extragalactic Astrophysics
Comment:		submitted to ApJ, 12 pages, 5 figures, 2 tables
Bibliographic Code:		2009arXiv0903.1258G

Abstract

We report on 5 Chandra observations of the X-ray afterglow of the Gamma-Ray Burst GRB 060729 performed between 2007 March and 2008 May. In all five observations the afterglow is clearly detected. The last Chandra pointing was performed on 2008-May-04, 642 days after the burst - the latest detection of a GRB X-ray afterglow ever. The last two Chandra observations in 2007 December and 2008 May clearly indicate a break at about one year after the burst. If interpreted as a jet break, this late-time break implies a jet half opening angle of ~14 degrees for a wind medium. On the other hand, the steep temporal decay and significant spectral softening after this break favor a spectral origin for the break. In the latter interpretation, no jet break was observed 642 days after the burst indicates the half-opening angle of the jet of GRB 060729 should be larger than >15 degrees for a wind medium. We compare the X-ray afterglow in a wind environment of GRB 060729 with other bright X-ray afterglows, in particular GRBs 061121 and 080319B, and discuss why the X-ray afterglow of GRB 060729 is such an exceptionally long-lasting event. A reanalysis of the Swift XRT light curve together with the three detections by Chandra in 2007 reveal a break at $\sim$1.2 Ms after the burst with a slight steepening of the decay slope from $\alpha$=1.32 to 1.65. This break coincides with a significant hardening of the X-ray spectrum, consistent with a cooling break in the wind medium scenario, in which the cooling frequency of the afterglow just crosses the X-ray band.

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