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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"

4066 results found.

  1. IPN triangulation of GRB 220411A
  2. IPN triangulation of short/soft GRB 220406A
  3. GRB 220310C: Swift/BAT-GUANO candidate arcminute localization
  4. IPN triangulation of GRB 220308A (long / very bright)
  5. IPN triangulation of GRB 220222A
  6. GCN Circ.draft on GRB 220222A
  7. ZTF22aabjpxh/AT2022cva: NICER X-ray detection is consistent with a GRB afterglow
  8. IPN triangulation of GRB 220219B (consistent with ZTF22aabjpxh/AT2022cva)
  9. ZTF22aaajecp/AT2022cmc: NICER X-ray detection
  10. IPN triangulation of GRB 220211A (short)
  11. IPN triangulation of a bright burst from SGR 1935+2154
  12. GRB 220107A: Swift/BAT-GUANO arcminute localization
  13. GRB 211229A: Swift/BAT-GUANO arcminute localization
  14. IPN triangulation of GRB 211130A
  15. GRB 211023A: optical observations and photometric evidence of supernova
  16. GRB 211107B: Swift/BAT detection
  17. GRB 211106A: Swift/BAT-GUANO candidate arcminute localization of a short burst
  18. GCN Viewer Now Available
  19. GRB 211024A: Swift/BAT-GUANO detection and candidate arcminute localization of a short burst
  20. IPN triangulation of GRB 210925B
  21. IPN triangulation of a bright burst from SGR 1935+2154
  22. GRB 210619B: Maidanak and Assy optical observations, broken power law parametrization
  23. GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
  24. IPN Triangulation of a bright burst from SGR 1935+2154
  25. GRB 210706A: Swift/BAT-GUANO detection and arcminute localization
  26. GRB 210619B: Deep CAHA 2.2m detection and late-time light curve behavior
  27. GRB 210626A: Swift/BAT-GUANO detection and arcminute localization
  28. IPN triangulation of GRB 210624A (short)
  29. GRB 210622A: Swift/BAT-GUANO detection and arcminute localization of a long burst
  30. GRB 210610A: CAHA 2.2m observations and light-curve behavior
  31. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  32. GRB 210606A: Swift/BAT-GUANO detection and arcminute localization
  33. GRB 210506A: Swift/BAT-GUANO detection and possible arcminute localization of a short hard burst
  34. IPN triangulation of GRB 210424B (short/hard)
  35. GRB 210421B: Swift/BAT-GUANO detection and arcminute localization
  36. GRB 210413B: Swift/BAT detection and probable localization of a short burst
  37. GRB210410A: Joint inspection of RATIR and D50 data
  38. GRB 210323B: Swift/BAT-GUANO detection and possible arcminute localization
  39. IceCube-201221A: Upper limits from Insight-HXMT/HE observations
  40. GRB 201216A: Swift/BAT-GUANO detection and arcminute localization
  41. IceCube-201209A: Upper limits from Insight-HXMT/HE observations
  42. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  43. GRB 201104C: Fermi GBM Final Real-time Localization
  44. GRB 201104A: Tiled Swift observations
  45. GRB 201103B: AGILE detection
  46. GRB 201104A: AGILE/MCAL detection
  47. GRB 201104A: Fermi-LAT detection
  48. GRB 201008A: Swift/BAT-GUANO detection and possible arcminute localization
  49. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  50. GRB 200714E: Swift/BAT-GUANO detection and arcminute localization
  51. GRB 200623A: Swift/BAT-GUANO detection and arcminute localization of a short GRB
  52. LIGO/Virgo MS200618aq: Retraction of a test binary neutron star candidate
  53. LIGO/Virgo MS200619bf: Retraction of a test binary neutron star candidate
  54. LIGO/Virgo MS200618bx: Retraction of a test binary neutron star candidate
  55. LIGO/Virgo MS200618bq: Retraction of a test binary neutron star candidate
  56. LIGO/Virgo MS200614ct: Identification of a test binary black hole candidate
  57. LIGO/Virgo MS200615ce: Identification of a test binary black hole candidate
  58. LIGO/Virgo MS200614bz: Test Identification of a binary neutron star candidate
  59. LIGO/Virgo MS200615h: Retraction of a test binary neutron star candidate
  60. IPN triangulation of GRB 200415A (possible Magnetar Giant Flare in Sculptor Galaxy?)
  61. IceCube-200410A : Upper limits from Insight-HXMT/HE observations
  62. IPN Triangulation of a bright burst from SGR 1935+2154
  63. LIGO/Virgo S200225q: Swift XRT observations, 1 X-ray sources
  64. LIGO/Virgo S200224ca: Swift XRT observations, 8 X-ray sources
  65. GRB 200405B: Swift/BAT-GUANO detection and *possible* arcminute localization of a short GRB
  66. LIGO/Virgo S200316bj: Upper limits from Konus-Wind observations
  67. LIGO/Virgo S200311bg: Upper limits from Konus-Wind observations
  68. LIGO/Virgo S200302c: Upper limits from Konus-Wind observations
  69. LIGO/Virgo S200225q: Upper limits from Konus-Wind observations
  70. LIGO/Virgo S200224ca: Upper limits from Konus-Wind observations
  71. IPN triangulation of GRB 200327A (short)
  72. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC-F30 observations
  73. LIGO/Virgo S200316bj: Updated Sky Localization and EM Bright Classification
  74. LIGO/Virgo S200316bj : No significant candidates in TAROT - FRAM - GRANDMA observations.
  75. LIGO/Virgo S200316bj: Upper limits from Insight-HXMT/HE observations
  76. LIGO/Virgo S200316bj: no counterpart candidate in SVOM/GWAC observations
  77. LIGO/Virgo S200316bj: Upper limits from CALET observations
  78. LIGO/Virgo S200316bj: No neutrino candidates at Pierre Auger Observatory
  79. LIGO/Virgo S200316bj: No counterpart candidates in Fermi-LAT observations
  80. LIGO/Virgo S200316bj: No Counterparts in DDOTI/OAN Optical Observations
  81. LIGO/Virgo S200316bj: no counterpart candidates in the Swift/BAT observations
  82. LIGO/Virgo S200213t: Continued Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
  83. LIGO/Virgo S200316bj: No counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  84. LIGO/Virgo S200316bj: upper limits from AGILE/GRID observations
  85. LIGO/Virgo S200316bj: upper limits from AGILE/MCAL observations
  86. LIGO/Virgo S200316bj: Upper limits from Fermi-GBM Observations
  87. LIGO/Virgo S200316bj: Coverage and upper limits from MAXI/GSC observations
  88. LIGO/Virgo S200316bj : no neutrino counterpart candidate in ANTARES search
  89. LIGO/Virgo S200316bj: Upper limits from IceCube neutrino searches
  90. LIGO/Virgo S200316bj: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo S200316bj: Global MASTER-Net observations report
  92. LIGO/Virgo S200311bg: Updated Sky Localization and EM Bright Classification
  93. LIGO/Virgo S200311bg: Not observable by CALET
  94. LIGO/Virgo S200311bg: Swift/BAT in the South Atlantic Anomaly
  95. LIGO/Virgo S200311bg: No significant counterpart candidates in Fermi-LAT observations
  96. LIGO/Virgo S200224ca: DESGW Summary of DECam Observations
  97. LIGO/Virgo S200311bg: not observable by Fermi GBM
  98. LIGO/Virgo S200311bg: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo S200311bg: not observable by AGILE at the event time
  100. LIGO/Virgo S200311bg: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation

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