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public:bggrbinfo [2019/02/16 01:02]
bruce [Synchrotron Emission Mechanism Theory (Encoded information in self-absorption frequency)] 		public:bggrbinfo [2023/09/12 12:04] (current)
bruce [X-rays]
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 ^GRB^Comment^ ^GRB^Comment^
 |080319b| **Prototype?** Naked Eye Burst, probably optically brightest, best optical light curve, proposed two-component jet (Racusin+08| |080319b| **Prototype?** Naked Eye Burst, probably optically brightest, best optical light curve, proposed two-component jet (Racusin+08|
-|11025A|**Prototype?** Very long burst, optical correlates better with MeV than KeV (Guiriec+16)|+|110205A|**Prototype?** Very long burst, optical correlates better with MeV than KeV (Guiriec+16)|
 |130427A|Largest E_ISO ever measured; 5.65e54  erg  (1 keV-10MeV); Fermi and Swift  -  Ref: GCN 14576 E_iso; Swift GCN 14448| |130427A|Largest E_ISO ever measured; 5.65e54  erg  (1 keV-10MeV); Fermi and Swift  -  Ref: GCN 14576 E_iso; Swift GCN 14448|
 |130603B| - short, Bright burst| |130603B| - short, Bright burst|
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 |160625B|**Prototype?** 3 episodes with different spectra;  Thermal, Band, PL  [[https://ui.adsabs.harvard.edu/#abs/arXiv:1612.03089|(Zhang, B. B-, 2018NatAs...2...69Z)]] | |160625B|**Prototype?** 3 episodes with different spectra;  Thermal, Band, PL  [[https://ui.adsabs.harvard.edu/#abs/arXiv:1612.03089|(Zhang, B. B-, 2018NatAs...2...69Z)]] |
 |GW170817| Short-GRB observed in LIGO/VIRGO, confirming for the first time NS inspiral model| |GW170817| Short-GRB observed in LIGO/VIRGO, confirming for the first time NS inspiral model|
-|190114C| brightest LAT event ever; detected by MAGIC at > 300 GeV GCN 23701; z=0.425|+|190114C| brightest LAT event ever; detected by MAGIC at > 300 GeV GCN 23701, intepreted as evidence for IC in GRB (Veres, P. 2019 Nature 575,459); z=0.425|
  
 ===== Z>6 list of GRB ===== ===== Z>6 list of GRB =====
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 *general-grb> *general-grb>
 +
 +*general-grb>Fundamentals
 +
 +===== Fundamentals - GRBs are beamed - The Inverse Compton Catastrophe =====
 +
 + 
 +There is a lot to this. There is an old standard radio astro thing called the Inverse Compton Catastrophe - that is that if Tb > 1e12K, a radio source , given equipartition of particle and mag energy, will radiate all its energy away in the X-rays in days, because so many electrons will be upscattered, and radiate rapidly at high E. 
 +
 +The paper Readhead 94, ApJ 426,51 "Equipartiion brightness temp and the IC Catastrophe" discusses this, and shows that they don't really see this, but rather a maximum Tb at 1e11K (rest).  
 +
 +He also notes that there are brightness temp.s estimated by variability time - because the timescale for the e- to "poop out" is a function of Tb.  This  drops rapidly with Tb = 1e11K; intra-day variability implies Tb ~ 1e12k at high radio freq; ~ 1e13k at low. Tb measured by interferometer is limited by the resolution; vblty time I think is more sensitive or allows higher. 
 +
 +Conclusion: Very high Tb will scatter electrons to very high energies, and the vblty time scale will be very, very short, and requires constant energy injection.  The way this is used is that if Tb> 1e12, and source is constant, it must be beamed.  
 +
 +I think there is another issue of pair production opacity, I did not see it in that paper. 
 +
 +keywords: Inverse Compton Catastrophe, brightness temperature limit, maximum brightness temperature, beaming. 
  
  
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 GRBs are often modeled as Band Functions - high-E and low-E power laws, but high-E is > 100 keV (for Fermi to observe)  so we are mostly concerned with low-E slope.   GRBs are often modeled as Band Functions - high-E and low-E power laws, but high-E is > 100 keV (for Fermi to observe)  so we are mostly concerned with low-E slope.  
 +
 +
 +Here is four years of GBM data BEST FIT N(E) slopes, a,  such that log slopes = 1+a.  NOTE that the figure is labeled "low-energy index" which is completely WRONG since an index implies a minus sign. 
 +
 +{{:public:best_fit_lowe_logslope_fermi.png?400|}}  This is from Gruber+14 https://arxiv.org/pdf/1401.5069.pdf
 +
 +
 +
 +
 Nava, L et al. 2010 arXiv: 1004.1410 http://arxiv.org/abs/1004.1410 says: Nava, L et al. 2010 arXiv: 1004.1410 http://arxiv.org/abs/1004.1410 says:
  
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 === Alternative Classifications to the Short vs. Long Classification Scheme: === === Alternative Classifications to the Short vs. Long Classification Scheme: ===
 +
 +At the GRB50 meeting there was a lot of talk of long GRBs apparently with Knovae, longs with no SNe, etc.  So the distinction is not that clear. 
 +
 +Here is a Girlanda paper asking if they are so different: https://www.sciencedirect.com/science/article/pii/S2214404815000129
    
  
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 To understand the various spectral components and the theoretical slopes, please see the section on [[public:emission|Emission Mechanism Theory]].  To understand the various spectral components and the theoretical slopes, please see the section on [[public:emission|Emission Mechanism Theory]]. 
  
-GRB 110205A: http://arxiv.org/abs/1111.0283 This paper looks like this burst 110205a might be one of the best observed ever, rivaling the Naked Eye Burst 080319B.+==== GRB 110205A ==== 
 + 
 +GRB 110205A was a 200 s duration GRB from z=2.2 that has really good data. 
 + 
 +http://arxiv.org/abs/1111.0283 This paper looks like this burst 110205a might be one of the best observed ever, rivaling the Naked Eye Burst 080319B. This paper claims it puts together multi-wavelength and makes FS+RS fit everything.  
 + 
 +==== GROND Prompt Measurement (but long delayed) ==== 
 + 
 +Eliot+13  arXiv:1312.5099 is a conference paper NOT PEER-REVIEW PUBLISHED about GRB121217 which had a delayed episode 700 seconds later!!!  Who knows how applicable this is to regular GRB, who knows if this is totally bogus but...   
 + 
 +Listen to this incredibly useful summary from abstract, "Only in a handful of cases has it been possible obtain simultaneous coverage of the prompt emission in a multi-wavelength regime (gamma-ray to optical), as a result of: observing the field by chance prior to the GRB (e.g. 080319B/naked-eye burst), long-prompt emission (e.g., 080928, 110205A) or triggered on a pre-cursor (e.g., 041219A, 050820A, 061121). [...And to this they now add 121217]" 
 + 
 + 
 +==== Other Papers ==== 
 +   
 + 
 +This oddly short little paper gives a kind of list of "all" prompt optical, and may be useful: http://www.sciencedirect.com/science/article/pii/S0273117710003972# 
  
-Other Papers:  This oddly short little paper gives a kind of list of "all" prompt optical, and may be useful: http://www.sciencedirect.com/science/article/pii/S0273117710003972# 
  
 BIggest collected study of prompt is Kopac+13 http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1305.6897, mostly ground-based. BIggest collected study of prompt is Kopac+13 http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1305.6897, mostly ground-based.
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 This paper  http://arxiv.org/abs/1306.3960v1  claims that SGRB are from Kilonova.  The evidence is maybe a little thin, but at least it's an interesting reference. This paper  http://arxiv.org/abs/1306.3960v1  claims that SGRB are from Kilonova.  The evidence is maybe a little thin, but at least it's an interesting reference.
 +
 +Later, however, [[public:gw170817|GW170817]] confirmed that NS-NS coalescence and resulting SNe are associated with SHGRB. 
 +
 +
 +===== ulGRBs - Ultralong GRBs =====
 +
 +GRB 111209a had a duratino of at least 7 hours. It had been proposed as a magneter powered SNe. The debate rages on as to whether or not UlGRBs are the tail of lGRBs or a separate class. 
 +
 +Boer+15 https://iopscience.iop.org/article/10.1088/0004-637X/800/1/16
 +
 +
  
  
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 There is also a very brief section mapping observations to theory. This is important in measurement of the BLF. There is also a very brief section mapping observations to theory. This is important in measurement of the BLF.
  
-== Correlations (possibly with z) == 
  
-The Amati, Ghirlanda, and Yonetoku relations are the most famous.  Many papers are out there, but '''many''' papers show that there is huge uncertainty and risk in using these correlations to get the red shift.  I can't believe that many people would take your work seriously, and reviewers would slaughter you.  +====== high-z GRB ======
- +
-Kocevski11:Kocevski, D.  2012, ApJ, 747, 146  http://arxiv.org/abs/1110.6173  - simulations of populations and accounting for instrument response shows how there is nothing physical in the correlations.  +
- +
-Shahmoradi&Nemiroff11:  Shahmoradi, A. & Nemiroff, R. J. 2011, MNRAS, 411, 1843  http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2010.17805.x/pdf or  http://arxiv.org/abs/0904.1464, same as above.  +
- +
-And again, http://arxiv.org/abs/1112.4347, Colazzi+ (includes schaefer & Preece), accepted to ApJ.  +
- +
- +
-'''A universal scaling for short and long gamma-ray bursts''':  E_{X,iso}-E_{gamma,iso}-E_{pk}  Bernardini, M. G.+12 , arXiv:1203.1060  (A universal scaling for short and long gamma-ray bursts: EX,iso - Eγ,iso - Epk, MNRAS, 425,  1199, M. G. Bernardini, R. Margutti, E. Zaninoni and G. Chincarini).    The big result is a search for correlations of everything yields the best correlations need to include some other parameter of the afterglow.   +
- +
-The paper above is supposedly based on the exhaustive analysis of Margutti, R. 12+ arXiv:1203.1059, (  http://mnras.oxfordjournals.org/content/early/2012/10/24/mnras.sts066.full  doi: 10.1093/mnras/sts066) but I see lots of data selection.+
  
-== high-z GRB == 
  
 Photo-z analysis suggests z~9.4 for GRB 090429B --- http://arxiv.org/abs/1105.4915, Cucchiara, A. et al. 2011, Astrophys. J. 736 (2011) 7 Photo-z analysis suggests z~9.4 for GRB 090429B --- http://arxiv.org/abs/1105.4915, Cucchiara, A. et al. 2011, Astrophys. J. 736 (2011) 7
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 Ellis&Mavromatos11.   http://arxiv.org/abs/1111.1178    L-Invariance and CTA Cherenkov Telescope Array. Ellis&Mavromatos11.   http://arxiv.org/abs/1111.1178    L-Invariance and CTA Cherenkov Telescope Array.
  
-== HECR_associated_with_GRB ==+====== HECR_associated_with_GRB ====== 
  
  
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 Spectra:  Spectra: 
 Mostly GRB have BAND function spectra, which can only sort-of be explained by a synchrotron emission mechanism. However, optical never quite fits these predictions. **ELIMINATED:** Synch. Self Compton (SSC) is eliminated in all observations, as Fermi-LAT has never seen the high energy upscattered part of that emission.  Mostly GRB have BAND function spectra, which can only sort-of be explained by a synchrotron emission mechanism. However, optical never quite fits these predictions. **ELIMINATED:** Synch. Self Compton (SSC) is eliminated in all observations, as Fermi-LAT has never seen the high energy upscattered part of that emission. 
 +
 +
 +===== Emission Time Evolution =====
 +
 +Of course prompt may be dominant in early emission but there could be evolution and phases of emission. 
 +
 +Lots of GRB are dominated by Reverse Shock, especially in the optical, rather than forward shock. This is most noticeable by smooth and round light curve structure, rather than spiky 980123b like light curve structure. 
 +
 +IN GRB 160625B. Nat Astron 2, 69–75 (2018). https://doi.org/10.1038/s41550-017-0309-8, the authors identified different gamma-ray spectra for a precursor 200 s before the burst, a blackbody or black body!!!, then band function during the usual burst, then a cutoff power law during time-extended emission 300-600 s after main burst. 
  
  
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 {{:public:screen_shot_2019-02-14_at_2.22.38_pm.png?200|}} {{:public:screen_shot_2019-02-14_at_2.22.38_pm.png?200|}}
 +
 +===== Inverse Compton Emission =====
 +
 +
 +This paper, on IC in prompt GRB emission, 
 +https://arxiv.org/abs/1901.05268 , Yue Zhang+19 ApJ, 877,89
 +abstract ends with "Therefore the ICS component is more likely to be detected for GRBs that have a hard low-energy photon spectrum."
 +
 +The paper says that big BLF <=> adiabatic expansion dominant cooling of e-s, <=> hard LE photon spectrum <=> Observable IC.
 +
 +NOTE:  IC NOT YET OBSERVED IN PROMPT - 190114C MAGIC ~ 1 TeV gammas intepreted as evidence for IC in GRB, but in AFTERGLOW (Veres, P. 2019 Nature 575,459).  The MAGIC light curve is clearly power law decay, not prompt.
 +
 +What are the prospects for observing prompt IC? What are the response times of Hess and Magic and Hawc?  Apparently, Magic, HESS responds to GCNs, as I believe do all atmospheric cerenkov telescopes.  ONLY HAWC has a wide FOV and is not steered, making it ideal for prompt, but it has yet to detect any GRBs. 
 +
 +HAWC - water cherenkov, not steered, so can measure prompt! FOV ~ 15% of sky (https://www.hawc-observatory.org)  No GRB detections yet.
 +
 +MAGIC - steered UV/opt  ???9 sq deg FOV - can't tell from website. 
 +
 +HESS - Stereoscopic UV/opt in Namibia, steered, one set of teles has 3.2 deg, one 5.0 deg on sky. 
  
 ===== Other components, multiple components, etc. ===== ===== Other components, multiple components, etc. =====
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-===== Cosmology Theory with GRB =====+====== Cosmology Theory with GRB ====== 
  
  
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 The paper above is supposedly based on the exhaustive analysis of Margutti, R. 12+ arXiv:1203.1059, ( http://mnras.oxfordjournals.org/content/early/2012/10/24/mnras.sts066.full doi: 10.1093/mnras/sts066) but I see lots of possible data selection. The paper above is supposedly based on the exhaustive analysis of Margutti, R. 12+ arXiv:1203.1059, ( http://mnras.oxfordjournals.org/content/early/2012/10/24/mnras.sts066.full doi: 10.1093/mnras/sts066) but I see lots of possible data selection.
 +
 +
 +== Correlations (possibly with z) ==
 +
 +The Amati, Ghirlanda, and Yonetoku relations are the most famous.  Many papers are out there, but '''many''' papers show that there is huge uncertainty and risk in using these correlations to get the red shift.  I can't believe that many people would take your work seriously, and reviewers would slaughter you. 
 +
 +Kocevski11:Kocevski, D.  2012, ApJ, 747, 146  http://arxiv.org/abs/1110.6173  - simulations of populations and accounting for instrument response shows how there is nothing physical in the correlations. 
 +
 +Shahmoradi&Nemiroff11:  Shahmoradi, A. & Nemiroff, R. J. 2011, MNRAS, 411, 1843  http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2010.17805.x/pdf or  http://arxiv.org/abs/0904.1464, same as above. 
 +
 +And again, http://arxiv.org/abs/1112.4347, Colazzi+ (includes schaefer & Preece), accepted to ApJ. 
 +
 +
 +'''A universal scaling for short and long gamma-ray bursts''':  E_{X,iso}-E_{gamma,iso}-E_{pk}  Bernardini, M. G.+12 , arXiv:1203.1060  (A universal scaling for short and long gamma-ray bursts: EX,iso - Eγ,iso - Epk, MNRAS, 425,  1199, M. G. Bernardini, R. Margutti, E. Zaninoni and G. Chincarini).    The big result is a search for correlations of everything yields the best correlations need to include some other parameter of the afterglow.  
 +
 +This is one of my favorite papers because it took a "computer-science"-like approach to analysis: correlated everything with everything and look at what might pop up.  Again, however, it really went further, it used correlations to determine if there were a THREE way correlation, or if two things were necessary to predict a third.  Let's try some keyword spam here: Margutti, Bernardini, correlation studies, gamma ray bursts, two-parameter correlation studies, computer-science approach. 
 +
 +The paper above is supposedly based on the exhaustive analysis of Margutti, R. 12+ arXiv:1203.1059, (  http://mnras.oxfordjournals.org/content/early/2012/10/24/mnras.sts066.full  doi: 10.1093/mnras/sts066) but I see lots of data selection.
public/bggrbinfo.1550278927.txt.gz · Last modified: 2021/01/12 00:50 (external edit)

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