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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"
  1. LIGO/Virgo S190425z: OVRO-LWA simultaneous low frequency radio observations of localization region
  2. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  3. LIGO/Virgo S190425z: ZTF19aarzaod Imaging from Las Cumbres Observatory
  4. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  5. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  6. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  7. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  8. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  9. LIGO/Virgo S190425z: LOAO Observation
  10. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  11. LIGO/Virgo S190425z: AGILE-GRID Observations
  12. LIGO/Virgo S190425z: Fermi GBM Observations
  13. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  14. LIGO/Virgo S190425z: SQUEAN Observation
  15. LIGO/Virgo S190425z: MMT Follow-Up Observations
  16. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  17. LIGO-Virgo S190425z: AGILE MCAL observation
  18. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  19. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  20. LIGO/Virgo S190425z: MAXI/GSC Observations
  21. LIGO/VIRGO S190425z: IceCube Neutrino Search
  22. LIGO/Virgo S190425z: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  23. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  24. LIGO/VirgoS190425z: HAWC follow-up
  25. LIGO/Virgo S190425z: SAGUARO follow-up observations
  26. LIGO/Virgo S190425z: Potential host galaxies from the GLADE catalog
  27. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  28. LIGO/Virgo S190425z: INTEGRAL prompt observation
  29. LIGO/Virgo S190425z: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo S190425z Global MASTER-Net observations report
  31. Fermi GRB190425.09 Global MASTER-Net observations report
  32. LIGO-Virgo S190421ar:Insight-HXMT/HE observation
  33. GRB 190424A: Swift-BAT refined analysis
  34. GRB 190424A: Swift detection of a burst
  35. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  36. GRB 190422A: Fermi GBM detection
  37. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  38. GRB 190422A: Swift/UVOT Upper Limits
  39. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  40. GRB 190422A: Swift-BAT refined analysis
  41. LIGO/Virgo S190421ar/G330308: ANTARES neutrino search
  42. GRB 190422A: Swift-XRT refined Analysis
  43. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  44. LIGO/Virgo S190421ar: MAXI/GSC Observations
  45. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  46. GRB 190422A: Enhanced Swift-XRT position
  47. Swift GRB190422.96 Global MASTER-Net observations report
  48. Fermi GRB190422.96 Global MASTER-Net observations report
  49. Fermi GRB190422.67 Global MASTER-Net observations report
  50. GRB 190422A: Swift detection of a burst
  51. LIGO/Virgo S190421ar: Fermi-GBM Observations
  52. LIGO/Virgo S190421ar Global MASTER-Net observations report
  53. LIGO/Virgo S190421ar: HAWC follow-up
  54. AT LIGO-Virgo S190421ar: AGILE GRID observations
  55. Subject: LIGO/VIRGO S190421ar: IceCube Neutrino Search
  56. LIGO/Virgo S190421ar: Identification of a GW compact binary merger candidate
  57. LIGO-Virgo S190421ar: AGILE MCAL observations
  58. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  59. Konus-Wind observation of GRB 190415A
  60. Fermi GRB190420.98 Global MASTER-Net observations report
  61. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  62. Fermi GRB190419.41 Global MASTER-Net observations report
  63. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
  64. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  65. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  66. Fermi GRB190418.92 Global MASTER-Net observations report
  67. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  68. GRB 190326A: Swift XRT and UVOT follow-up observations
  69. IPN Triangulation of GRB 190415A
  70. Fermi GRB190417.46 Global MASTER-Net observations report
  71. LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
  72. GRB 190415A: Insight-HXMT/HE detection
  73. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  74. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  75. Fermi GRB190415.17 Global MASTER-Net observations report
  76. GRB 190407B: AstroSat CZTI detection
  77. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  78. LIGO/Virgo S190412m: Palomar Gattini-IR Wide-field Infrared Follow-up
  79. GRB 190411A: AstroSat CZTI detection
  80. GRB 190411A: Insight-HXMT/HE detection
  81. LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
  82. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  83. LIGO/Virgo S190412m: Swift/BAT data search
  84. LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
  85. LIGO/Virgo S190412m: Fermi-GBM Observations
  86. LIGO/Virgo S190412m: MAXI/GSC Observations
  87. LIGO-Virgo S190412m: AGILE GRID observations
  88. LIGO/Virgo S190405ar: Retraction of a GW binary merger candidate
  89. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  90. LIGO/Virgo S190408an: ATLAS observations of the S190412m skymap
  91. LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidate
  92. LIGO/Virgo S190412m/G329483: ANTARES neutrino search
  93. LIGO/Virgo S190412m: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  94. LIGO-Virgo S190412m: Search for neutrino counterparts with IceCube
  95. LIGO/Virgo S190412m: HAWC follow-up
  96. INTEGRAL prompt observation of S190412m
  97. LIGO-Virgo S190412m: AGILE preliminary analysis
  98. LIGO/Virgo S190412m: MASTER early alert observation
  99. LIGO/Virgo S190412m: Identification of a GW binary merger candidate
  100. LIGO/Virgo S190408an: GROND Observations of MASTER OT J154209.55-431742.2

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