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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"

4067 results found.

  1. LIGO/Virgo S191216ap: Coverage and upper limits from MAXI/GSC observations
  2. LIGO/Virgo S191216ap: Upper limits from Fermi-GBM Observations
  3. LIGO/Virgo S191216ap: 1 counterpart neutrino candidate from IceCube neutrino searches
  4. LIGO/Virgo S191216ap : no neutrino counterpart candidate in ANTARES search
  5. LIGO/Virgo S191216ap: Global MASTER-Net observations report
  6. LIGO/Virgo S191216ap: no INTEGRAL observation
  7. LIGO/Virgo S191216ap: No counterpart candidates in HAWC observations
  8. LIGO/Virgo S191216ap: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo S191215w: no counterpart candidates in the Swift/BAT observations
  10. LIGO/Virgo S191215w: No counterpart candidates in Fermi-LAT observations
  11. UKIRT photometry of ZTF19acyldun/AT 2019wrt
  12. LIGO/Virgo S191215w: AstroSat CZTI upper limits
  13. LIGO/Virgo S191215w: upper limits from AGILE-GRID observations
  14. LIGO/Virgo S191215w: upper limits from AGILE/MCAL observations
  15. LIGO/Virgo S191215w: Upper limits from Fermi-GBM Observations
  16. LIGO/Virgo S191215w: No counterpart candidates in HAWC observations
  17. LIGO/Virgo S191215w: Coverage and upper limits from MAXI/GSC observations
  18. LIGO/Virgo S191215w : no neutrino counterpart candidate in ANTARES search
  19. LIGO/Virgo S191215w: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  20. LIGO/Virgo S191215w: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo S191215w: Global MASTER-Net observations report
  22. LIGO/Virgo S191215w: Upper limits from IceCube neutrino searches
  23. LIGO/Virgo S191213g: Additional candidates from the Zwicky Transient Facility
  24. LIGO/Virgo S191213g: Upper limits from Insight-HXMT/HE observations
  25. LIGO/Virgo S191213g: LCOGT photometry of ZTF19acymaru/AT2019wnh
  26. LIGO/Virgo S191213g: Lulin Follow-up Observations of ZTF19acykzsk/AT2019wqj
  27. LIGO/Virgo S191213g: Pan-STARRS1 previous detections of ZTF19acykzsk
  28. LIGO/Virgo S191213g: WHT spectroscopy of candidate counterparts
  29. LIGO/Virgo S191213g: GRAWITA TNG classification of ZTF19acykzsk
  30. LIGO/Virgo S191213g: GMOS-N spectroscopy shows ZTF19acykzsk/AT2019wqj is a SN II
  31. LIGO/Virgo S191213g: Liverpool Telescope spectroscopy of ZTF candidates
  32. LIGO/Virgo S191213g: AstroSat CZTI upper limits
  33. LIGO/Virgo S191213g: Candidates from the Zwicky Transient Facility
  34. LIGO/Virgo S191213g: No neutrino candidates at Pierre Auger Observatory
  35. LIGO/Virgo S191205ah: AT2019wix and AT2019wib 10.4m GTC spectroscopy
  36. LIGO/Virgo S191205ah: AT2019wkv, AT2019wid and AT2019wiy 10.4m GTC spectroscopy
  37. LIGO/Virgo S191213g: No transient candidates in CALET observations
  38. LIGO/Virgo S191213g: Updated Sky Localization
  39. LIGO/Virgo S191205ah: Candidates from the Zwicky Transient Facility Public Survey
  40. LIGO/Virgo S191213ai: Retraction of GW compact binary merger candidate
  41. LIGO/Virgo S191213g: No counterpart candidates in Fermi-LAT observations
  42. LIGO/Virgo S191213ai: Global MASTER-Net observations report
  43. LIGO/Virgo S191213g: no counterpart candidates in the Swift/BAT observations
  44. LIGO/Virgo S191213g: Upper limits from Fermi-GBM Observations
  45. LIGO/Virgo S191213g: upper limits from AGILE-GRID observations
  46. LIGO/Virgo S191213g: upper limits from AGILE-MCAL observations
  47. LIGO/Virgo S191205ah: AT2019wfa 10.4m GTC spectroscopy
  48. LIGO/Virgo S191213g : no neutrino counterpart candidate in ANTARES search
  49. LIGO/Virgo S191213g: Coverage and upper limits from MAXI/GSC observations
  50. LIGO/Virgo S191213g: Identification of a GW compact binary merger candidate
  51. LIGO/Virgo S191213g: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  52. LIGO/Virgo S191213g: Global MASTER-Net observations report
  53. LIGO/Virgo S191213g: Upper limits from IceCube neutrino searches
  54. LIGO/Virgo S191205ah: Gaia Photometric Alerts transient candidates
  55. LIGO/Virgo S191204r: correction to GRAWITA GCN 26390
  56. LIGO/Virgo S191212q: Retraction of GW compact binary merger candidate
  57. LIGO/Virgo S191212q: Global MASTER-Net observations report
  58. LIGO/Virgo S191204r: GRAWITA VST-ESO PARANAL transient candidates discovery.
  59. LIGO/Virgo S191205ah: no counterpart candidate in SVOM/GWAC observations
  60. LIGO/Virgo S191205ah : No significant candidates in FRAM - TAROT – GRANDMA observations
  61. LIGO/Virgo S191129u: Updated Sky Localization
  62. LIGO/Virgo S191205ah: MASTER OT 1.5m OSN imaging and 10.4m GTC spectroscopy
  63. LIGO/Virgo S191205ah: MITSuME Observation of MASTER OT J123123.61-043847.2
  64. LIGO/Virgo S191204r: GRAWITA VST-ESO PARANAL observations.
  65. LIGO/Virgo S191205ah: MASTER OT detection
  66. LIGO/Virgo S191205ah: Not observable by CALET
  67. LIGO/Virgo S191205ah: AstroSat CZTI upper limits
  68. IceCube-191204A : Upper limits from Insight-HXMT/HE observations
  69. LIGO/Virgo S191205ah: Upper limits from Insight-HXMT/HE observations
  70. LIGO/Virgo S191204r: Upper limits from Insight-HXMT/HE observations
  71. LIGO/Virgo S191205ah: No neutrino candidates at Pierre Auger Observatory
  72. LIGO/Virgo S191205ah: GMG detection of SAGUARO transient
  73. LIGO/Virgo S191205ah: no counterpart candidates in the Swift/BAT observations
  74. LIGO/Virgo S191205ah: Pan-STARRS1 previous detections of SAGUARO transient
  75. LIGO/Virgo S191205ah: No counterpart candidates in Fermi-LAT observations
  76. LIGO/Virgo S191129u : No significant candidates in FRAM-TAROT-GRANDMA observations.
  77. LIGO/Virgo S191204r: No significant candidates in FRAM-TAROT-GRANDMA observations.
  78. LIGO/Virgo S191205ah: SAGUARO observations and identification of an optical candidate
  79. LIGO/Virgo S191205ah: Upper limits from Fermi-GBM Observations
  80. LIGO/Virgo S191204r: No transient candidates in CALET observations
  81. LIGO/Virgo S191204r: No counterpart candidates in Fermi-LAT observations
  82. LIGO/Virgo S191205ah: Coverage and upper limits from MAXI/GSC observations
  83. LIGO/Virgo S191205ah: upper limits from AGILE-MCAL observations
  84. LIGO/Virgo S191205ah: No counterpart candidates in HAWC observations
  85. LIGO/Virgo S191205ah: Global MASTER-Net observations report
  86. LIGO/Virgo S191205ah : no neutrino counterpart candidate in ANTARES search
  87. LIGO/Virgo S191205ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  88. LIGO/Virgo S191205ah: Identification of a GW compact binary merger candidate
  89. LIGO/Virgo S191205ah: Upper limits from IceCube neutrino searches
  90. LIGO/Virgo S191204r: no counterpart candidates in the Swift/BAT observations
  91. LIGO/Virgo S191204r: not observable by Fermi-GBM
  92. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  93. LIGO/Virgo S191204r: upper limits from AGILE-GRID observations
  94. LIGO/Virgo S191204r: upper limits from AGILE-MCAL observations
  95. LIGO/Virgo S191204r : no neutrino counterpart candidate in ANTARES search
  96. LIGO/Virgo S191204r: Upper limits from IceCube neutrino searches
  97. LIGO/Virgo S191204r: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo S191204r: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  99. LIGO/Virgo S191204r: Global MASTER-Net observations report
  100. LIGO/Virgo S191129u: No transient candidates in CALET observations

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