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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"

27301 results found.

  1. LIGO/Virgo S190425z: Nearby Galaxies in the Updated Localization Volume
  2. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  3. LIGO/Virgo S190425z: ZTF pre-merger limits on PS1 candidates
  4. LIGO/Virgo S190425z: CALET Observations
  5. LIGO/Virgo S190425z - ePESSTO+ spectrum of PS19qp shows red featureless source at z=0.037
  6. LIGO/Virgo S190425z - ePESSTO+ NTT spectrum of candidate PS19qo
  7. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  8. LIGO/Virgo S190425z - ePESSTO+ NTT observations
  9. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  10. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  11. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  12. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  13. LIGO/Virgo S190425z: Fermi GBM Observations
  14. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  15. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  16. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  17. LIGO/Virgo S190425z: MAXI/GSC Observations
  18. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  19. LIGO/VirgoS190425z: HAWC follow-up
  20. LIGO/Virgo S190425z: SAGUARO follow-up observations
  21. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  22. LIGO/Virgo S190425z: INTEGRAL prompt observation
  23. LIGO/Virgo S190425z Global MASTER-Net observations report
  24. Fermi GRB190425.09 Global MASTER-Net observations report
  25. GRB 190424A: Swift-BAT refined analysis
  26. GRB 190424A: Swift detection of a burst
  27. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  28. GRB 190422A: Fermi GBM detection
  29. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  30. GRB 190422A: Swift/UVOT Upper Limits
  31. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  32. GRB 190422A: Swift-BAT refined analysis
  33. GRB 190422A: Swift-XRT refined Analysis
  34. LIGO/Virgo S190421ar: MAXI/GSC Observations
  35. Swift GRB190422.96 Global MASTER-Net observations report
  36. Fermi GRB190422.96 Global MASTER-Net observations report
  37. Fermi GRB190422.67 Global MASTER-Net observations report
  38. GRB 190422A: Swift detection of a burst
  39. LIGO/Virgo S190421ar: Fermi-GBM Observations
  40. LIGO/Virgo S190421ar Global MASTER-Net observations report
  41. LIGO/Virgo S190421ar: HAWC follow-up
  42. Fermi GRB190420.98 Global MASTER-Net observations report
  43. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  44. Fermi GRB190419.41 Global MASTER-Net observations report
  45. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  46. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  47. Fermi GRB190418.92 Global MASTER-Net observations report
  48. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  49. IPN Triangulation of GRB 190415A
  50. Fermi GRB190417.46 Global MASTER-Net observations report
  51. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  52. GRB 190415A: Insight-HXMT/HE detection
  53. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  54. Fermi GRB190415.17 Global MASTER-Net observations report
  55. GRB 190411A: Insight-HXMT/HE detection
  56. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  57. LIGO/Virgo S190412m: Swift/BAT data search
  58. LIGO/Virgo S190412m: Fermi-GBM Observations
  59. LIGO/Virgo S190412m: MAXI/GSC Observations
  60. LIGO/Virgo S190405ar: Retraction of a GW binary merger candidate
  61. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  62. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  63. LIGO/Virgo S190412m: HAWC follow-up
  64. LIGO/Virgo S190412m: MASTER early alert observation
  65. LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
  66. IPN triangulation of GRB 190409B (short)
  67. GRB 190409A: ground analysis reveals a likely spurious event
  68. LIGO/Virgo S190408an: MAXI/GSC Observations
  69. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  70. LIGO/Virgo S190408an: CALET Observations
  71. LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
  72. Konus-Wind observation of GRB 190404B
  73. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  74. GRB 190409A: Swift detection of a possible burst
  75. LIGO-Virgo S190408an: further AGILE GRID observations after T0
  76. LIGO/Virgo S190408an: SAGUARO follow-up observations
  77. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  78. LIGO/Virgo S190408an: Swift/BAT data search
  79. LIGO-Virgo S190408an: AGILE GRID observations
  80. LIGO-Virgo S190408an: HAWC follow-up
  81. LIGO/Virgo S190408an: Fermi GBM Observation
  82. Fermi Gamma-ray Burst Monitor trigger 576420743/190408536 is not a GRB
  83. Fermi Trigger 576356086 / GRB 190407788 / : BALROG localization
  84. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  85. Fermi Trigger 576346051 / GRB 190407672 / GRB 190407A: BALROG localization
  86. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  87. Swift GRB 190331B: Further Swift-XRT observations
  88. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  89. Trigger 896552: Swift detection of PSR B1055-52
  90. GRB 190401A: Insight-HXMT/HE detection
  91. GRB 190331C: Insight-HXMT/HE detection
  92. GRB 190331A: Insight-HXMT/HE detection
  93. GRB 190330A: Insight-HXMT/HE detection
  94. GRB 190329A: CALET Gamma-Ray Burst Monitor detection
  95. GRB 190331A: Fermi GBM detection
  96. GRB 190331A, Swift-BAT refined analysis
  97. IPN Triangulation of GRB 190329A (long/bright)
  98. GRB 190331A: Swift detection of a burst
  99. Fermi Trigger 575656777 / GRB 190330694 / GRB 190330A: BALROG localization
  100. MAGIC follow-up of the X-ray flares of LS I +61�303 dete

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