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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

12191 results found.

  1. Swift GRB200306.01: Global MASTER-Net observations report
  2. GRB 200228B: continued optical observations
  3. Konus-Wind observation of GRB200303A
  4. LIGO/Virgo S200302c: AstroSat CZTI upper limits
  5. GRB 200303A: Swift-XRT refined Analysis
  6. Swift GRB200303.11: Global MASTER-Net observations report
  7. Fermi trigger No 604895668: Global MASTER-Net observations report
  8. LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations
  9. LIGO/Virgo S200302c: No counterpart candidates in KAIT observations
  10. LIGO/Virgo S200302c: No counterpart candidates in HAWC observations
  11. LIGO/Virgo S200225q: AstroSat CZTI upper limits
  12. LIGO/Virgo S200219ac: AstroSat CZTI upper limits
  13. LIGO/Virgo S200302c: Coverage and upper limits from MAXI/GSC observations
  14. LIGO/Virgo S200225q : No significant candidates in TAROT - FRAM - GRANDMA observations.
  15. GRB 200228B: Swift-XRT refined Analysis
  16. GRB 200228B: KAIT Optical Upper Limit
  17. Fermi-LAT Gamma-ray Observations of IceCube-200227A
  18. GRB 200227A: Insight-HXMT/HE detection
  19. GRB 200227A: Fermi GBM observation
  20. LIGO/Virgo S200224ca : No significant candidates in TAROT - FRAM - GRANDMA observations
  21. IceCube-200227A: IceCube observation of a high-energy neutrino candidate event
  22. GRB 200227A: Swift detection of a burst
  23. GRB 200227A: Fermi GBM Final Real-time Localization
  24. Konus-Wind observation of GRB 200219C
  25. Konus-Wind observation of GRB 200219A
  26. LIGO/Virgo S200219ac: Upper limits from Konus-Wind observations
  27. LIGO/Virgo S200213t: Upper limits from Konus-Wind observations
  28. LIGO/Virgo S200208q: Upper limits from Konus-Wind observations
  29. LIGO/Virgo S200225q: no counterpart candidate in SVOM/GWAC observations
  30. LIGO/Virgo S200224ca: No counterpart candidates in KAIT observations
  31. LIGO/Virgo S200224ca: GRAWITA-Campo Imperatore observations.
  32. Fermi trigger No 604231129: Global MASTER-Net observations report
  33. LIGO/Virgo S200225q: No counterpart candidates in Fermi-LAT observations
  34. LIGO/Virgo S200225q: No counterpart candidates in HAWC observations
  35. LIGO/Virgo S200225q: Global MASTER-Net observations report
  36. LIGO/Virgo S200224ca: No counterpart candidates in Fermi-LAT observations
  37. LIGO/Virgo S200225q: Coverage and upper limits from MAXI/GSC observations
  38. LIGO/Virgo S200224ca: Coverage and upper limits from MAXI/GSC observations
  39. GRB 200224A: Swift-XRT refined Analysis
  40. Fermi trigger No 604213554: Global MASTER-Net observations report
  41. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  42. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  43. LIGO/Virgo S200219ac : No significant candidates in TAROT - FRAM - GRANDMA observations.
  44. GRB 200219A: FRAM-Auger optical limit
  45. GRB 200219C: Mondy and TSHAO optical observations
  46. GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
  47. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  48. GRB 200219C: DDOTI Observations
  49. LIGO/Virgo S200213t: AT2020clw/ZTF20aanaoyz, AT2020crd/ZTF20aanakge and AT2020cly/ZTF20aanakes 10.4m GTC spectroscopy
  50. LIGO/Virgo S200213t: Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
  51. GRB 200219C: Fermi-LAT detection
  52. GRB 200219A, Swift-BAT refined analysis
  53. Fermi trigger No 603849435: Global MASTER-Net observations report
  54. LIGO/Virgo S200219ac: No counterpart candidates in Fermi-LAT observations
  55. GRB 200219A: Swift-XRT refined Analysis correction
  56. LIGO/Virgo S200219ac: No counterpart candidates in HAWC observations
  57. LIGO/Virgo S200219ac: Coverage and upper limits from MAXI/GSC observations
  58. GRB 200219A: Swift detection of a short burst
  59. Swift GRB200219.32: Global MASTER-Net observations report
  60. GRB 200216B: Mondy and AbAO optical upper limits
  61. GRB 200216B: Swift-XRT refined Analysis
  62. LIGO/Virgo S200213t : No significant candidates in FRAM - OAJ - TAROT - GRANDMA observations
  63. LIGO/Virgo S200213t: AstroSat CZTI upper limits
  64. GRB 200216B: Swift detection of a burst
  65. Swift GRB200216.56: Global MASTER-Net observations report
  66. LIGO/Virgo S200213t: Updated coverage and candidate list for the Zwicky Transient Facility
  67. LIGO/Virgo S200213t: CLU/NED Galaxies in the 4-Update Localization Volume
  68. LIGO/Virgo S200213t: Possible host galaxies in the bilby skymap
  69. GRB 200215A: Liverpool Telescope upper limits
  70. Swift GRB200215.61: Global MASTER-Net observations report
  71. GRB 200215A: Swift detection of a burst
  72. LIGO/Virgo S200213t: MASTER possible Kilonova candidate in PGC315337
  73. LIGO/Virgo S200213t: No counterpart candidates from Nanshan-0.6m observations
  74. LIGO/Virgo S200213t: More Candidates from the Zwicky Transient Facility
  75. LIGO/Virgo S200213t: No counterpart candidates in KAIT observations
  76. LIGO/Virgo S200213t: AT2020ciz/ZTF20aamvnat, AT2020cjb/ZTF20aamvnth and 2020cjf/ZTF20aamvodd 10.4m GTC spectroscopy
  77. LIGO/Virgo S200213t: No counterpart candidates in Fermi-LAT observations
  78. LIGO/Virgo S200213t: No Counterparts in DDOTI/OAN Optical Observations
  79. LIGO/Virgo S200213t: AT2020ciy/ZTF20aamvqxl, AT2020cjg/ZTF20aamvoxx and AT2020cje/ZTF20aamvtip 10.4m GTC spectroscopy
  80. LIGO/Virgo S200213t: MANGROVE catalog galaxy ranking
  81. LIGO/Virgo S191213g: AT2019wxt Wendelstein optical observations
  82. LIGO/Virgo S200208q : No significant candidates in TAROT - FRAM - GRANDMA observations
  83. LIGO/Virgo S200213t: Coverage and upper limits from MAXI/GSC observations
  84. LIGO/Virgo trigger S200213t: Possible host galaxies
  85. LIGO/Virgo S200213t: NED Galaxies in the 90% Localization Volume
  86. ZTF20aajnksq: Upper limits from Konus-Wind observations
  87. GRB 200131A: Tautenburg observations
  88. Konus-Wind observation of GRB 200205B
  89. LIGO/Virgo S200208q: No counterpart candidates in KAIT observations
  90. LIGO/Virgo S200208q: No counterpart candidates in Fermi-LAT observations
  91. GRB 200120A: Fermi GBM observation
  92. LIGO/Virgo S200208q: Coverage and upper limits from MAXI/GSC observations
  93. LIGO/Virgo S200208q: No counterpart candidates in HAWC observations
  94. Fermi trigger No 602817262: Global MASTER-Net observations report
  95. GRB 200205B: Swift-BAT refined analysis
  96. Fermi trigger No 602731380: Global MASTER-Net observations report
  97. GRB 200205B: Swift-XRT refined Analysis
  98. GRB 200205B: LCO Optical Detection
  99. GRB 200205C: Fermi GBM Final Real-time Localization
  100. GRB 200205B: Swift detection of a burst with optical counterpart

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