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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

4258 results found.

  1. LIGO/Virgo G274296: Observations of initial skymap by project Mini-GWAC of SVOM
  2. GRB 170214A: Fermi GBM detection
  3. IPN Triangulation of GRB 170209A
  4. LIGO/Virgo G270580: AstroSat CZTI upper limits
  5. LIGO/Virgo G270580: Gemini-South Spectroscopic Classification of Optical Transients
  6. Konus-Wind observation of GRB 170206A
  7. GRB 170202A: MITSuME Akeno Optical Observation
  8. GRB 170202A: MASTGlobal ER-Net bright OT nonmonotonic light curve
  9. GRB 170202A : Xinglong TNT optical observation
  10. GRB 170202A: Swift detection of a burst with an optical afterglow
  11. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  12. LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
  13. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  14. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  15. LIGO/Virgo G270580: Observations of initial skymap by Project Mini-GWAC of SVOM
  16. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  17. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  18. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  19. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  20. LIGO/Virgo G268556: VLA follow-up of ATLAS17aeu
  21. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  22. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  23. GRB 161220A: Swift-XRT refined Analysis
  24. GRB 161220A: Swift detection of a burst
  25. GRB 161219B: Swift detection of a burst with an optical afterglow
  26. GRB 161129A: KWFC z-band photometry
  27. GRB 161129A: Mondy optical observations
  28. GRB 161129A: ISON/UAFO optical observations
  29. GRB 161129A: MITSuME Okayama Ks-band Observation
  30. GRB 161129A: MITSuME Okayama Optical Observation
  31. GRB 161129A: Tautenburg Ic-band observations
  32. GRB 161129A: TSHAO optical observations / possible afterglow+host galaxy
  33. GRB 161117A: Swift/UVOT Detection
  34. GRB 161117A: VLT/X-shooter spectroscopy and redshift
  35. GRB 161117A: Swift detection of a burst with an optical counterpart
  36. Fermi GBM trigger 499467682/161029876 is not a GRB
  37. GRB 161014A: Swift detection of a burst
  38. GRB 160925A: Kottamia R-band observation
  39. GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
  40. Konus-Wind observation of GRB 160910A
  41. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  42. Fermi GBM trigger 494508549 / 160902479 is not a GRB
  43. GRB 160829A: Fermi GBM Detection
  44. GRB 160829A: Fermi-LAT detection of a short GRB
  45. GRB 160825A: not localized by Swift
  46. GRB 160821B: Swift-BAT refined analysis
  47. GRB 160821B: Fermi GBM Detection
  48. GRB 160821B: Swift detection of a short burst
  49. GRB 160821A: Swift detection of a bright burst
  50. GRB 160816A: confirmed fading with the LT
  51. GRB 160816A: RATIR Optical and NIR Observations
  52. GRB 160816A: LCOGT-FTN optical candidate
  53. GRB 160816A: Swift-XRT afterglow detection
  54. GRB 160801A: SAO RAS optical observations
  55. GRB 160801A: NOT upper limits
  56. GRB 160801A: Swift-BAT refined analysis
  57. Global MASTER net follow up of IceCube-160731A
  58. GRB 160801A: Enhanced Swift-XRT position
  59. GRB 160801A: Swift detection of a burst
  60. GBM observation of SGR-like burst from the direction of PSR 1119-6127
  61. Trigger 706396: Swift detection of a short burst from PSR 1119-6127
  62. GRB 160703, GRB 160705, GRB 160720, SGR1935+2154: First SGRs and GRBs detected by Lomonosov.
  63. GRB 160714A: MASTER early optical observations
  64. GRB 160714A: Optical observations from OSN
  65. GRB 160625B: TSHAO optical observations
  66. GRB 160709A: Global MASTER Net Fermi GBM Alerts observations
  67. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  68. GRB 160625B: RTT150 optical observations
  69. Konus-Wind observation of GRB 160703A
  70. GRB 160625B: SAO RAS monitoring
  71. GRB 160629A: Global MASTER Net Prompt OT observations
  72. GRB 160629A: BTA and GTC redshift
  73. GRB 160629A: a long GBB detected by INTEGRAL
  74. Konus-Wind observation of a bright burst from SGR 1935+2154
  75. SGR 1935+2154: AMI 15 GHz upper limits of the magnetar during outburst
  76. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  77. Swift-BAT refined analysis on the bright event from SGR 1935+2154
  78. Trigger 701590: Swift detection of a bright outburst from SGR 1935+2154
  79. GRB 160624A: Prompt enhanced Swift-XRT position
  80. GROND observations of GRB 160622A/SNR RCW 103/SGR 1617-5103
  81. Trigger 701182: Swift detection of SGR 1935+2154
  82. SGR 1617-5103 (BAT trigger 700791): Enhanced Swift-XRT position.
  83. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  84. Fermi GBM Trigger 160622573 is not a GRB
  85. GRB 160622A: Swift detection of a possible short GRB or a new SGR
  86. More FERMI GBM bursts from the magnetar SGR 1935+2154
  87. SGR 1935+2154: MAXI/GSC detection
  88. Fermi GBM trigger 488128598/160620637 is not a GRB
  89. Fermi GBM trigger 487974449/160618852 is not a GRB
  90. GRB 160521A: 15 GHz detections and upper limit from AMI
  91. Trigger 689956: Swift detection of a source near the Galactic center
  92. Trigger 689353 (possible transient near Sgr A*), Swift-BAT refined analysis
  93. Trigger 689353: Swift detection of a transient near Sgr A*
  94. Fermi GBM trigger 486562774/160602514 is not a GRB
  95. GRB 160601A: GTC observations confirming transient source decay
  96. GRB 160601A: Swift detection of a short hard burst
  97. Another Swift detection of SGR 1935+2154 (trigger #687124)
  98. Swift detection of SGR 1935+2154
  99. Konus-Wind observation of a bright burst from SGR 1935+2154
  100. FERMI GBM bursts from the magnetar SGR 1935+2154

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