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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"

3163 results found.

  1. IPN triangulation of GRB 200311A
  2. Fermi trigger No 605756501: Global MASTER-Net observations report
  3. Fermi trigger No 605632577: Global MASTER-Net observations report
  4. GRB 200311A: Fermi GBM Final Real-time Localization
  5. GRB 200306C: Swift-BAT refined analysis
  6. Swift GRB200306.95: Global MASTER-Net observations report
  7. Swift GRB200306.95: Global MASTER-Net OT detection
  8. LIGO/Virgo S200302c : No significant candidates in FRAM - TAROT - GRANDMA observations.
  9. LIGO/Virgo S200302c: No counterpart candidates in KAIT observations
  10. LIGO/Virgo S200224ca: Transient found in Swift/UVOT counterpart search
  11. LIGO/Virgo S200302c: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  12. LIGO/Virgo S200225q : No significant candidates in TAROT - FRAM - GRANDMA observations.
  13. GRB 200228B: LCO Optical Upper Limit
  14. LIGO/Virgo S200224ca : No significant candidates in TAROT - FRAM - GRANDMA observations
  15. LIGO/Virgo S200225q: no counterpart candidate in SVOM/GWAC observations
  16. LIGO/Virgo S200224ca: No Counterparts in DDOTI/OAN Optical Observations
  17. Fermi trigger No 604231129: Global MASTER-Net observations report
  18. GRB 200224A: BOOTES-1 and 1.5m OSN optical observations
  19. Swift GRB200224.14: Global MASTER-Net observations report
  20. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  21. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC observations
  22. LIGO/Virgo S200219ac : No significant candidates in TAROT - FRAM - GRANDMA observations.
  23. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  24. LIGO/Virgo S200213t: AT2020clw/ZTF20aanaoyz, AT2020crd/ZTF20aanakge and AT2020cly/ZTF20aanakes 10.4m GTC spectroscopy
  25. LIGO/Virgo S200219ac: Coverage and upper limits from MAXI/GSC observations
  26. GRB 200219B: Fermi GBM Final Real-time Localization
  27. LIGO/Virgo (S200213t/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  28. LIGO/Virgo S200213t : No significant candidates in FRAM - OAJ - TAROT - GRANDMA observations
  29. LIGO/Virgo S200213t: Updated coverage and candidate list for the Zwicky Transient Facility
  30. LIGO/Virgo S200213t: More Candidates from the Zwicky Transient Facility
  31. LIGO/Virgo S200213t: No counterpart candidates in KAIT observations
  32. LIGO/Virgo S200213t: AT2020ciz/ZTF20aamvnat, AT2020cjb/ZTF20aamvnth and 2020cjf/ZTF20aamvodd 10.4m GTC spectroscopy
  33. LIGO/Virgo S200208q : No significant candidates in TAROT - FRAM - GRANDMA observations
  34. LIGO/Virgo S200208q: no counterpart candidate in SVOM/C-GFT observations
  35. LIGO/Virgo S200213t: Coverage and upper limits from MAXI/GSC observations
  36. LIGO/Virgo S200208q: No counterpart candidates in KAIT observations
  37. LIGO/Virgo S200208q: Global MASTER-Net observations report
  38. Fermi trigger No 602817262: Global MASTER-Net observations report
  39. MAXI GRB200205.29: Global MASTER-Net observations report
  40. GRB 200131A: Swift detection of a burst with an optical counterpart
  41. Swift GRB200131.95: Global MASTER-Net observations report
  42. LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations
  43. LIGO/Virgo S200128d : No significant candidates in FRAM - TAROT - GRANDMA observations
  44. LIGO/Virgo S200128d: No counterpart candidates in KAIT observations
  45. LIGO/Virgo S200128d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  46. GRB 200125A: Swift-BAT refined analysis
  47. GRB 200127A: Swift detection of a burst
  48. Fermi trigger No 601729856: Global MASTER-Net observations report
  49. Fermi trigger No 601677816: Global MASTER-Net observations report
  50. GRB 200125B: Fermi GBM Final Real-time Localization
  51. LIGO/Virgo S200114f : No significant candidates in TAROT - FRAM - GRANDMA observations
  52. Fermi trigger No 601363105: Global MASTER-Net observations report
  53. GRB 200122A: Swift detection of a burst
  54. GRB 200120A: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo S200115j : No significant candidates in TAROT - FRAM - GRANDMA observations
  56. LIGO/Virgo S200105ae: More candidates from the Zwicky Transient Facility
  57. GRB 200115A: AROMA-N Optical Observation
  58. LIGO/Virgo S200112r : No significant candidates in TAROT - FRAM - GRANDMA observations.
  59. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  60. Baksan Neutrino Observatory Alert 200116.21: Global MASTER-Net observations report
  61. IPN triangulation of GRB 200111A
  62. LIGO/Virgo S200114f: No counterpart in targeted WHT/ACAM imaging
  63. LIGO/Virgo S200115j: Revised list of possible host galaxies with the new skymap
  64. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  65. Fermi trigger No 600666048: Global MASTER-Net observations report
  66. IceCube-200107A: Upper limits from a search for additional neutrino events in IceCube
  67. IceCube Alert 200109.99: Global MASTER-Net observations report
  68. IceCube Alert 200109.99: Global MASTER-Net observations report
  69. LIGO/Virgo S200105ae : No significant candidates in TAROT - FRAM - GRANDMA observations.
  70. GRB 200107B: Swift-XRT refined Analysis
  71. Fermi-LAT ANTARES coincidence
  72. Swift GRB 200107B: Global MASTER-Net observations report
  73. GRB 200107B: Swift-BAT refined analysis
  74. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  75. IceCube-200107A: No significant detection in HAWC
  76. IceCube-200107A: No candidates from the Zwicky Transient Facility
  77. IceCube-200107A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  78. GRB 200107B: Swift detection of a burst
  79. IceCube-200107A: IceCube observation of a high-energy neutrino candidate event
  80. LIGO/Virgo S200105ae: Global MASTER-Net observations report
  81. GRB 200105A: MAXI/GSC detection
  82. Fermi trigger No 599761015: Global MASTER-Net observations report
  83. IceCube Alert 200101.46: Global MASTER-Net observations report
  84. Fermi trigger No 599603971: Global MASTER-Net observations report
  85. IPN triangulation of GRB 191227B (short)
  86. GRB 191227A: Swift detection of a burst
  87. LIGO/Virgo S191205ah: MASTER OT detection
  88. LIGO/Virgo S191222n : No significant candidates in FRAM-TAROT-GRANDMA observations
  89. LIGO/Virgo S191222n: no counterpart candidate in SVOM/GWAC observations
  90. LIGO/Virgo S191213g : No significant candidates found in GRANDMA citizen science observations
  91. LIGO/Virgo S191222n: upper limits from AGILE-GRID observations
  92. Baksan Neutrino Observatory Alert 191222.09: Global MASTER-Net observations report
  93. LIGO/Virgo S191216ap: MASTER optical observation
  94. LIGO/Virgo S191216ap : No significant candidates in FRAM-TAROT-GRANDMA observations
  95. Konus-Wind observation of GRB 191218A
  96. LIGO/Virgo S191213g: Lulin Follow-up Observations of AT2019wxt
  97. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  98. GRB 191218A: AstroSat CZTI detection
  99. GRB 191218A: Swift detection of a burst
  100. LIGO/Virgo S191216ap and IceCube neutrino: Swift XRT sources

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