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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.

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

11848 results found.

  1. GRB 200101A: BALROG localization (Fermi Trigger 599603971 / GRB 200101861)
  2. GRB 200101A: Fermi GBM Final Real-time Localization
  3. IceCube-191231A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  4. GRB 191221B: CALET Gamma-Ray Burst Monitor detection
  5. Konus-Wind observation of GRB 191227A
  6. Konus-Wind observation of GRB 191227B
  7. IPN triangulation of GRB 191227B (short)
  8. GRB 191228A: Swift-XRT refined Analysis
  9. LIGO/Virgo S191216ap: Two candidate counterparts from UKIRT/WFCAM z-band observations
  10. GRB 191228A: Swift detection of a burst
  11. Swift GRB191228.00: Global MASTER-Net observations report
  12. GRB 191227A: Marginal detection by Fermi-LAT
  13. Swift GRB191227.07: Global MASTER-Net observations report
  14. LIGO/Virgo S191213g: AT2019wxt 10.4m GTC further spectroscopy
  15. Swift GRB191226.25: Global MASTER-Net observations report
  16. Swift GRB191226.02: Global MASTER-Net observations report
  17. Konus-Wind observation of GRB 191221B
  18. LIGO/Virgo S191222n : No significant candidates in FRAM-TAROT-GRANDMA observations
  19. GRB 191221B: Swift/UVOT Detection
  20. LIGO/Virgo S191222n: no counterpart candidate in SVOM/GWAC observations
  21. GRB 191220.59: AstroSat CZTI detection
  22. GRB 191221B: AstroSat CZTI detection
  23. GRB 191221B: Swift-XRT refined Analysis
  24. LIGO/Virgo S191213g : No significant candidates found in GRANDMA citizen science observations
  25. LIGO/Virgo S191222n: No counterpart candidates in Fermi-LAT observations
  26. GRB 191221B: MASTER VWFC OT yearly detection
  27. GRB 191221B: Correction to GCN26551 - VIRT OT observation
  28. GRB 191221B: VIRT Optical Upper Limits
  29. GRB 191221B: AGILE/MCAL observations
  30. LIGO/Virgo S191222n: Coverage and upper limits from MAXI/GSC observations
  31. LIGO/Virgo S191222n: No counterpart candidates in HAWC observations
  32. Baksan Neutrino Observatory Alert 191222.09: Global MASTER-Net observations report
  33. GRB 191221B: Swift detection of a burst and a very bright optical candidate
  34. Fermi trigger No 598648473: Global MASTER-Net observations report
  35. LIGO/Virgo S191216ap: No radio candidates so far in the VLA/JAGWAR galaxy targeted search
  36. LIGO/Virgo S191216ap: MASTER optical observation
  37. LIGO/Virgo S191216ap : No significant candidates in FRAM-TAROT-GRANDMA observations
  38. LIGO/Virgo S191213g: VLA follow-up of AT2019wxt/PS19hg
  39. GRB 191220A: AbAO optical observations
  40. Fermi trigger No 598543714: Global MASTER-Net observations report
  41. LIGO/Virgo S191213g: DCT observation of AT2019wxt
  42. GRB 191220A: Swift detection of a burst
  43. Swift GRB191220.56: Global MASTER-Net observations report
  44. LIGO/Virgo S191220af: Global MASTER-Net observations report
  45. LIGO/Virgo S191216ap: AstroSat CZTI upper limits
  46. LIGO/Virgo S191216ap: Subaru/Hyper Suprime-Cam observations of GW+IceCube+HAWC error region
  47. Konus-Wind observation of GRB 191218A
  48. LIGO/Virgo S191216ap, Swift XRT observations: 16 X-ray sources in the HAWC error region search
  49. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  50. LIGO/Virgo S191216ap: No candidates found in CHES observations of HAWC error region
  51. Konus-Wind observation of GRB 191213A (ulong)
  52. LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region
  53. LIGO/Virgo S191216ap and IceCube neutrino: Swift XRT sources
  54. LIGO/Virgo S191215w : No significant candidates in TAROT - FRAM - GRANDMA observations.
  55. LIGO/Virgo G191216ap: No counterpart candidates in Fermi-LAT observations
  56. LIGO/Virgo S191216ap: Coverage and upper limits from MAXI/GSC observations
  57. Fermi-LAT Gamma-ray Observations of IceCube-191215A
  58. LIGO/Virgo S191216ap: Global MASTER-Net observations report
  59. LIGO/Virgo S191216ap: No counterpart candidates in HAWC observations
  60. LIGO/Virgo S191215w: No counterpart candidates in Fermi-LAT observations
  61. LIGO/Virgo S191215w: AstroSat CZTI upper limits
  62. LIGO/Virgo S191215w: No counterpart candidates in HAWC observations
  63. LIGO/Virgo S191215w: Coverage and upper limits from MAXI/GSC observations
  64. IceCube Alert 191215.47: Global MASTER-Net observations report
  65. LIGO/Virgo S191213g: Lulin Follow-up Observations of ZTF19acykzsk/AT2019wqj
  66. LIGO/Virgo S191213g: GRAWITA TNG classification of ZTF19acykzsk
  67. LIGO/Virgo S191213g: AstroSat CZTI upper limits
  68. LIGO/Virgo S191213g: No counterpart candidates in Fermi-LAT observations
  69. Fermi trigger No 597909938: Global MASTER-Net observations report
  70. LIGO/Virgo S191213g: Coverage and upper limits from MAXI/GSC observations
  71. Baksan Neutrino Observatory Alert 191211.1: Global MASTER-Net observations report
  72. Possible HAWC-detected GRB 191210A: Fermi-LAT Upper Limits
  73. Possible HAWC-detected GRB 191210A: Swift-XRT observations
  74. LIGO/Virgo S191205ah: no counterpart candidate in SVOM/GWAC observations
  75. GRB 191207A: Possible GRB detected in Fermi-LAT blind search
  76. LIGO/Virgo S191205ah : No significant candidates in FRAM - TAROT – GRANDMA observations
  77. LIGO/Virgo S191205ah: MASTER OT 1.5m OSN imaging and 10.4m GTC spectroscopy
  78. LIGO/Virgo S191204r: GRAWITA VST-ESO PARANAL observations.
  79. LIGO/Virgo S191205ah: AstroSat CZTI upper limits
  80. Fermi-LAT Gamma-ray Observations of IceCube-191204A
  81. LIGO/Virgo S191205ah: No counterpart candidates in Fermi-LAT observations
  82. LIGO/Virgo S191129u : No significant candidates in FRAM-TAROT-GRANDMA observations.
  83. LIGO/Virgo S191204r: No significant candidates in FRAM-TAROT-GRANDMA observations.
  84. LIGO/Virgo S191204r: No counterpart candidates in Fermi-LAT observations
  85. LIGO/Virgo S191205ah: Coverage and upper limits from MAXI/GSC observations
  86. LIGO/Virgo S191205ah: No counterpart candidates in HAWC observations
  87. LIGO/Virgo S191205ah: Global MASTER-Net observations report
  88. LIGO/Virgo S191204r: no counterpart candidates in the Swift/BAT observations
  89. GRB 191205A: Fermi GBM Final Real-time Localization
  90. IceCube-191204A: Upper limits from Fermi-GBM Observations
  91. Konus-Wind observation of GRB191202A
  92. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  93. GRB 191202A: Fermi-LAT detection
  94. GRB 191202A: Fermi GBM observation
  95. GRB 191202A: AstroSat CZTI detection
  96. GRB 191202A: Fermi GBM Final Real-time Localization
  97. LIGO/Virgo S191129u: No counterpart candidates in Fermi-LAT observations
  98. LIGO/Virgo S191129u: No counterpart candidates in HAWC observations
  99. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  100. GRB 191125B: MASTER-VWFC synchronous observation

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