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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"

4059 results found.

  1. LIGO/Virgo S190425z: Fermi GBM Observations
  2. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  3. LIGO/Virgo S190425z: SQUEAN Observation
  4. LIGO/Virgo S190425z: MMT Follow-Up Observations
  5. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  6. LIGO-Virgo S190425z: AGILE MCAL observation
  7. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  8. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  9. LIGO/Virgo S190425z: MAXI/GSC Observations
  10. LIGO/VIRGO S190425z: IceCube Neutrino Search
  11. LIGO/Virgo S190425z: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  12. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  13. LIGO/VirgoS190425z: HAWC follow-up
  14. LIGO/Virgo S190425z: SAGUARO follow-up observations
  15. LIGO/Virgo S190425z: Potential host galaxies from the GLADE catalog
  16. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  17. LIGO/Virgo S190425z: INTEGRAL prompt observation
  18. LIGO/Virgo S190425z: Identification of a GW compact binary merger candidate
  19. LIGO/Virgo S190425z Global MASTER-Net observations report
  20. LIGO-Virgo S190421ar:Insight-HXMT/HE observation
  21. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  22. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  23. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  24. LIGO/Virgo S190421ar/G330308: ANTARES neutrino search
  25. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  26. LIGO/Virgo S190421ar: MAXI/GSC Observations
  27. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  28. LIGO/Virgo S190421ar: Fermi-GBM Observations
  29. LIGO/Virgo S190421ar Global MASTER-Net observations report
  30. LIGO/Virgo S190421ar: HAWC follow-up
  31. AT LIGO-Virgo S190421ar: AGILE GRID observations
  32. LIGO/VIRGO S190421ar: IceCube Neutrino Search
  33. LIGO/Virgo S190421ar: Identification of a GW compact binary merger candidate
  34. LIGO-Virgo S190421ar: AGILE MCAL observations
  35. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  36. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  37. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  38. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  39. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  40. LIGO/Virgo S190412m: Palomar Gattini-IR Wide-field Infrared Follow-up
  41. LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
  42. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  43. LIGO/Virgo S190412m: Swift/BAT data search
  44. LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
  45. LIGO/Virgo S190412m: Fermi-GBM Observations
  46. LIGO/Virgo S190412m: MAXI/GSC Observations
  47. LIGO-Virgo S190412m: AGILE GRID observations
  48. LIGO/Virgo S190405ar: Retraction of a GW binary merger candidate
  49. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  50. LIGO/Virgo S190408an: ATLAS observations of the S190412m skymap
  51. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  52. LIGO/Virgo S190412m/G329483: ANTARES neutrino search
  53. LIGO/Virgo S190412m: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  54. LIGO-Virgo S190412m: Search for neutrino counterparts with IceCube
  55. LIGO/Virgo S190412m: HAWC follow-up
  56. LIGO-Virgo S190412m: AGILE preliminary analysis
  57. LIGO/Virgo S190412m: MASTER early alert observation
  58. LIGO/Virgo S190412m: Identification of a GW binary merger candidate
  59. LIGO/Virgo S190408an: GROND Observations of MASTER OT J154209.55-431742.2
  60. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  61. LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
  62. LIGO/Virgo S190408an: MAXI/GSC Observations
  63. LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
  64. LIGO/Virgo S190408an: CALET Observations
  65. LIGO/Virgo S190408an: TMTS Optical Observation
  66. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  67. LIGO/Virgo S190408an: HMT optical observations
  68. LIGO/Virgo S190408an: MASTER 3 OT's more detection
  69. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  70. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  71. LIGO/Virgo S190408an: SAGUARO follow-up observations
  72. LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
  73. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  74. LIGO/Virgo S190408an: MASTER OT detection
  75. LIGO/Virgo S190408an: Swift/BAT data search
  76. LIGO/Virgo S190408an: KMTNet observation
  77. LIGO-Virgo S190408an: AGILE GRID observations
  78. LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
  79. LIGO/Virgo S190408an: Identification of a GW binary merger candidate
  80. LIGO-Virgo S190408an: HAWC follow-up
  81. LIGO/Virgo S190408an: Fermi GBM Observation
  82. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  83. LIGO-Virgo S190408an: AGILE MCAL observations
  84. LIGO/Virgo: Announcing the start of Observing Run 3 (O3) and the beginning of the public gravitational-wave alert era
  85. IPN Triangulation of GRB 190329A (long/bright)
  86. GRB 190114C: photometric detection of a SN component
  87. Improved Fermi/GBM GRB localizations
  88. IPN Triangulation of GRB 190304A (long)
  89. IPN Triangulation of GRB 190206A (short/extremely bright)
  90. GRB 190204A: Swift-BAT refined analysis
  91. IPN Triangulation of GRB 190129B (long/extremely bright)
  92. IPN Triangulation of GRB 190118A (long)
  93. CALET Gamma-Ray Burst Monitor: Policy change in the GCN circulars
  94. INTEGRAL observations of the events in the GWTC-1 catalog
  95. Fermi-GBM Observations During Four New GW-Detected BBH Mergers (Correction)
  96. Fermi-GBM Observations During Four New GW-Detected BBH Mergers
  97. IPN Triangulation of GRB 181121A (short)
  98. GRB 180728B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 554505003)
  99. GRB180913A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 558557292)
  100. IPN Triangulation of GRB 181008B (long)

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