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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').
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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"

8523 results found.

  1. LIGO/Virgo S191216ap: No candidates found in CHES observations of HAWC error region
  2. LIGO/Virgo S191216ap and IceCube neutrino: no counterpart candidates from AGILE-GRID observations
  3. LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region
  4. LIGO/Virgo S191216ap: CORRECTED list of galaxies coincident with LIGO/Virgo and HAWC positions
  5. LIGO/Virgo S191216ap: Nanshan follow-up observations
  6. LIGO/Virgo S191213g: MASTER OT J064855.37-055545.7 is a dwarf nova
  7. LIGO/Virgo S191216ap: No Candidates from the Zwicky Transient Facility
  8. LIGO/Virgo S191216ap: Correction to GCN 26460 (IceCube event coincident with GW event)
  9. LIGO/Virgo S191216ap: Upper limits from Fermi-GBM Observations
  10. LIGO/Virgo S191216ap: 1 counterpart neutrino candidate from IceCube neutrino searches
  11. Fermi-LAT Gamma-ray Observations of IceCube-191215A
  12. LIGO/Virgo S191216ap : no neutrino counterpart candidate in ANTARES search
  13. LIGO/Virgo S191216ap: No counterpart candidates in HAWC observations
  14. LIGO/Virgo S191216ap: Identification of a GW compact binary merger candidate
  15. IceCube-191215A: Upper limits from a search for additional neutrino events in IceCube
  16. UKIRT photometry of ZTF19acyldun/AT 2019wrt
  17. LIGO/Virgo S191215w: upper limits from AGILE-GRID observations
  18. LIGO/Virgo S191215w: Upper limits from Fermi-GBM Observations
  19. LIGO/Virgo S191215w: No counterpart candidates in HAWC observations
  20. LIGO/Virgo S191215w : no neutrino counterpart candidate in ANTARES search
  21. LIGO/Virgo S191215w: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S191215w: Upper limits from IceCube neutrino searches
  23. IceCube-191215A: not observable by Fermi-GBM
  24. IceCube-191215A - IceCube observation of a high-energy neutrino candidate event
  25. LIGO/Virgo S191213g: LCOGT photometry of ZTF19acymaru/AT2019wnh
  26. LIGO/Virgo S191213g: Lulin Follow-up Observations of ZTF19acykzsk/AT2019wqj
  27. LIGO/Virgo S191213g: WHT spectroscopy of candidate counterparts
  28. LIGO/Virgo S191213g: GRAWITA TNG classification of ZTF19acykzsk
  29. LIGO/Virgo S191213g: Candidates from the Zwicky Transient Facility
  30. LIGO/Virgo S191213g: Updated Sky Localization
  31. LIGO/Virgo S191205ah: Candidates from the Zwicky Transient Facility Public Survey
  32. LIGO/Virgo S191213ai: Retraction of GW compact binary merger candidate
  33. LIGO/Virgo S191213g: Upper limits from Fermi-GBM Observations
  34. LIGO/Virgo S191213g: upper limits from AGILE-GRID observations
  35. LIGO/Virgo S191213g : no neutrino counterpart candidate in ANTARES search
  36. LIGO/Virgo S191213g: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo S191213g: Upper limits from IceCube neutrino searches
  38. LIGO/Virgo S191205ah: Gaia Photometric Alerts transient candidates
  39. LIGO/Virgo S191212q: Retraction of GW compact binary merger candidate
  40. Possible HAWC-detected GRB 191210A: Fermi-LAT Upper Limits
  41. Possible HAWC-detected GRB 191210A: no neutrino counterpart candidate in ANTARES search
  42. LIGO/Virgo S191205ah: no counterpart candidate in SVOM/GWAC observations
  43. LIGO/Virgo S191129u: Updated Sky Localization
  44. LIGO/Virgo S191205ah: Not observable by CALET
  45. LIGO/Virgo S191205ah: AstroSat CZTI upper limits
  46. IceCube-191204A: No significant detection in HAWC
  47. LIGO/Virgo S191205ah: GMG detection of SAGUARO transient
  48. LIGO/Virgo S191205ah: SAGUARO observations and identification of an optical candidate
  49. LIGO/Virgo S191205ah: Upper limits from Fermi-GBM Observations
  50. LIGO/Virgo S191205ah: No counterpart candidates in HAWC observations
  51. LIGO/Virgo S191205ah : no neutrino counterpart candidate in ANTARES search
  52. LIGO/Virgo S191205ah: Identification of a GW compact binary merger candidate
  53. LIGO/Virgo S191205ah: Upper limits from IceCube neutrino searches
  54. IceCube-191204A: Upper limits from Fermi-GBM Observations
  55. IceCube-191204A - IceCube observation of a high-energy neutrino candidate event
  56. LIGO/Virgo S191204r: upper limits from AGILE-GRID observations
  57. LIGO/Virgo S191204r : no neutrino counterpart candidate in ANTARES search
  58. LIGO/Virgo S191204r: Upper limits from IceCube neutrino searches
  59. LIGO/Virgo S191204r: Identification of a GW compact binary merger candidate
  60. GRB 191130A: Swift ToO observations
  61. GRB 191004A: correction to reported GROND upper limits
  62. LIGO/Virgo S191129u: No counterpart candidates in HAWC observations
  63. LIGO/Virgo S191129u: upper limits from AGILE/GRID observations
  64. LIGO/Virgo S191129u : no neutrino counterpart candidate in ANTARES search
  65. LIGO/Virgo S191129u: Upper limits from IceCube neutrino searches
  66. LIGO/Virgo S191129u: Identification of a GW compact binary merger candidate
  67. IceCube-191122A: No significant detection in HAWC
  68. IceCube-191122A: Not observable by Fermi-GBM
  69. IceCube-191122A: Upper limits from a search for additional neutrino events in IceCube
  70. LIGO/Virgo S191124be: Retraction of GW compact binary merger candidate
  71. GRB 191123A: Swift/UVOT detection
  72. GRB 191123A: Swift detection of a burst with an optical counterpart
  73. IceCube-191122A - IceCube observation of a high-energy neutrino candidate event
  74. GRB 191122A: CHES Optical Observations
  75. GRB 191122A: Swift detection of a burst
  76. IceCube-191119A: No significant detection in HAWC
  77. IceCube-191119A: No neutrino counterpart candidates in ANTARES search
  78. LIGO/Virgo S191120at: Retraction of GW compact binary merger candidate
  79. LIGO/Virgo S191120aj: Retraction of GW compact binary merger candidate
  80. IceCube-191119A: Upper limits from a search for additional neutrino events in IceCube
  81. IceCube-191119A: Upper limits from Fermi-GBM Observations
  82. IceCube-191119A - IceCube observation of a high-energy neutrino candidate event
  83. LIGO/Virgo S191117j: Retraction of GW compact binary merger candidate
  84. Swift Trigger 937114 is not an astrophysical source
  85. LIGO/Virgo S191110af: Retraction of GW unmodeled transient candidate
  86. LIGO/Virgo S191110af: Upper limits from KM3NeT MeV neutrino search.
  87. GRB 191027A: CALET Gamma-Ray Burst Monitor detection
  88. LIGO/Virgo S191105e: Updated Sky Localization
  89. LIGO/Virgo S191110af: Potential pulsar counterparts
  90. LIGO/Virgo S191110af: Upper limits from CALET observations.
  91. LIGO/Virgo S191109d: Not observable by CALET
  92. LIGO/Virgo S191110af: Upper limits from IceCube MeV neutrino searches
  93. LIGO/Virgo S191110af: No neutrino counterpart candidate in ANTARES search
  94. LIGO/Virgo S191110af: Upper limits from Fermi-GBM Observations
  95. LIGO/Virgo S191110af: Identification of a GW unmodeled transient candidate
  96. LIGO/Virgo S191110af: Upper limits from IceCube neutrino searches
  97. LIGO/Virgo S191110x: Retraction of GW compact binary merger candidate
  98. LIGO/Virgo S191109d : no neutrino counterpart candidate in ANTARES search
  99. LIGO/Virgo S191109d: upper limits from AGILE-GRID observations mailed-by:
  100. LIGO/Virgo S191109d: Upper limits from Fermi-GBM Observations

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