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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 S190519bj Global MASTER-Net observations report
  2. LIGO/Virgo S190519bj: Fermi GBM Observations
  3. LIGO-Virgo S190519bj: AGILE GRID observations
  4. LIGO/Virgo S190519bj: AGILE MCAL observations
  5. LIGO/Virgo S190519bj: ANTARES neutrino search
  6. LIGO/Virgo S190519bj: HAWC follow-up
  7. LIGO/Virgo S190519bj: INTEGRAL SPI/ACS prompt observation
  8. LIGO/Virgo S190519bj: IceCube Neutrino Search
  9. LIGO/Virgo S190519bj: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo S190517h: CALET Observations
  11. LIGO/Virgo S190426c: NICER X-ray Follow-Up of ZTF19aassfws
  12. LIGO/Virgo S190518bb: Retraction of GW compact binary merger candidate
  13. LIGO/Virgo S190518bb Global MASTER-Net observations report
  14. LIGO/Virgo S190517h: INTEGRAL prompt observation
  15. LIGO/Virgo S190512at: Updated sky localization
  16. LIGO/Virgo S190517h: Fermi-LAT search for a high-energy gamma-ray counterpart
  17. LIGO/Virgo S190517h: Swift/BAT Counterpart Search
  18. LIGO/Virgo S190517h: ANTARES neutrino search
  19. LIGO/Virgo S190517h: Insight-HXMT/HE observations
  20. LIGO/Virgo S190517h: Fermi GBM Observations
  21. LIGO/Virgo S190517h: HAWC follow-up
  22. LIGO/Virgo S190517h: MAXI/GSC Observations
  23. LIGO/Virgo S190517h Global MASTER-Net observations report
  24. LIGO-Virgo S190517h: AGILE GRID observations
  25. LIGO/Virgo S190517h: IceCube Neutrino Search
  26. LIGO/Virgo S190517h: AGILE MCAL observations
  27. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  28. LIGO/Virgo S190517h: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo S190513bm: Swope follow-up observations
  30. LIGO/Virgo S190426c: AMI-LA radio observations of ZTF19aassfws
  31. LIGO/Virgo S190513bm : TAROT-Calern and TAROT-Chile (TCA/TCH)/GRANDMA observation report.
  32. LIGO/Virgo S190513bm: CALET Observations
  33. LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
  34. LIGO/Virgo S190503bf: Gaia Photometric Alerts transient candidate
  35. LIGO/Virgo S190510g: Gaia Photometric Alerts transient candidate
  36. LIGO/Virgo S190513bm: Swift/BAT Counterpart Search
  37. LIGO/Virgo S190513bm: Insight-HXMT/HE observation
  38. LIGO/Virgo S190510g: Swift-XRT observations and results
  39. LIGO/Virgo S190510g: DECam-GROWTH optical counterpart candidate DG19qcso
  40. LIGO/Virgo S190513bm: ANTARES neutrino search
  41. LIGO/Virgo S190513bm: Fermi GBM Observations
  42. LIGO/Virgo S190510g: AT2019ezb and AT2019far 10.4m GTC spectroscopy
  43. LIGO/Virgo S190513bm: Fermi-LAT search for a high-energy gamma-ray counterpart
  44. LIGO/Virgo S190512at: CALET Observations
  45. LIGO/Virgo S190513bm: MAXI/GSC Observations
  46. LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
  47. LIGO/Virgo S190513bm: AGILE GRID observations
  48. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  49. LIGO/Virgo S190513bm: AGILE MCAL observation
  50. LIGO/Virgo S190513bm Global MASTER-Net observations report
  51. LIGO/Virgo S190513bm: IceCube Neutrino Search
  52. LIGO/Virgo S190513bm: HAWC follow-up
  53. LIGO/Virgo S190513bm: Identification of a GW compact binary merger candidate
  54. LIGO/Virgo S190512at: Insight-HXMT/HE observation
  55. LIGO-Virgo S190512at: AGILE GRID observations
  56. LIGO/Virgo S190512at: Swift/BAT Counterpart Search
  57. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  58. LIGO/Virgo S190512at: ANTARES neutrino search
  59. LIGO/Virgo S190512at: Fermi-LAT search for a high-energy gamma-ray counterpart
  60. LIGO/Virgo S190512at: MAXI/GSC Observations
  61. LIGO/Virgo S190512at: Fermi GBM Observations
  62. LIGO/Virgo S190512at Global MASTER-Net observations report
  63. LIGO/Virgo S190510g: Spectroscopic Classification of DECam-GROWTH and DES-GW Candidate DG19fqqk/desgw-190510c with Magellan
  64. LIGO/Virgo S190510g: MASTER OT detection inside PGC087378 galaxy
  65. LIGO/Virgo S190512at: INTEGRAL inactive at the time of the event
  66. LIGO-Virgo S190512at: AGILE MCAL observations
  67. LIGO/Virgo S190512at: IceCube Neutrino Search
  68. LIGO/Virgo S190512at: Identification of a GW compact binary merger candidate
  69. IPN triangulation of GRB 190510A (short)
  70. LIGO/Virgo S190510g: DOAO Observation
  71. LIGO/Virgo S190510g: CALET Observations
  72. LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
  73. LIGO/Virgo S190510g: OT MASTER142812.05-013615.2 retraction as the kilonova candidate in GCN 24490
  74. LIGO/Virgo S190510g: MASTER OT detection inside low surface brightness galaxy
  75. LIGO/Virgo S190510g: Update on candidate significance
  76. LIGO/Virgo S190510g: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  77. LIGO/Virgo S190510g: Non-detection of the OT in PGC 094244
  78. LIGO/Virgo S190426c: VLA Follow-Up Observations of ZTF19aassfws
  79. LIGO/Virgo S190510g: GRAWITA REM and Loiano optical observations
  80. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  81. LIGO/Virgo S190510g: DESGW counterpart candidates over 80% of the GW localization area
  82. LIGO/Virgo S190510g : Xinglong-60cm upper limit of the GRAWITA REM's OT
  83. LIGO/Virgo S190510g: MASTER OT independ detection in WISE J060606.26-353233.9 galaxy at desgw-190510a position.
  84. LIGO/Virgo S190510g: Unconfirmed OT in PGC 094244
  85. LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
  86. LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
  87. LIGO/Virgo S190510g: DESGW counterpart candidate (desgw-190510a)
  88. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  89. LIGO/Virgo S190510g: MASTER possible OT in PGC094244 galaxy
  90. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  91. LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
  92. LIGO/Virgo S190510g: Optical Counterpart Candidates from DECam-GROWTH
  93. LIGO/Virgo S190510g: KMTNet observation
  94. LIGO/Virgo S190510g: CNEOST Follow-Up Observations
  95. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  96. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
  97. LIGO/Virgo S190510g: Updated classification and data quality report
  98. LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
  99. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  100. LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source

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