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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24615 results found.

  1. GRB 190427A: MITSuME Akeno optical upper limits
  2. LIGO/Virgo S190426c: Infrared Wide-field Search with Palomar Gattini-IR
  3. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  4. LIGO/Virgo S190426c: Insight-HXMT/HE observation
  5. LIGO/Virgo S190426c: Updated localization to fix data format issue
  6. LIGO/Virgo S190426c: Updated localization from LIGO and Virgo data
  7. LIGO/Virgo S190426c: CALET Observations
  8. LIGO/Virgo S190426c: Imaging confirmation and host spectroscopy of DG19vkgf
  9. LIGO/Virgo S190425z: Lulin Observations of Counterpart Search
  10. ANTARES follow-up of the GW candidate S190426c
  11. LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
  12. LIGO/Virgo S190426c: Red and blue transients identified with DECam
  13. LIGO/Virgo S190425z: Lijiang 2.4-m Telescope Follow-up Observations
  14. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  15. Swift GRB190427.19 Global MASTER-Net observations report
  16. GRB 190427A: Swift detection of a short burst
  17. LIGO/Virgo S190426c: MAXI/GSC Observations
  18. LIGO/Virgo S190426c: Public DECam Observations
  19. LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
  20. LIGO/Virgo S190426c: Swift/BAT Counterpart Search
  21. LIGO/Virgo S190426c: STARE2 simultaneous L-band radio observations
  22. LIGO/Virgo S190426c: a possible lensed NS-NS merger
  23. LIGO/Virgo S190426c: Tentative Red Transient Candidate from Las Cumbres Observatory
  24. LIGO/Virgo S190426c: Fermi GBM Observations
  25. LIGO/Virgo S190426c: SAO optical observation
  26. LIGO/Virgo S190426c: AGILE-GRID Observations
  27. LIGO-Virgo S190426c: AGILE MCAL observation
  28. LIGO/Virgo S190425z: Further MMT Follow-Up Observations
  29. LIGO/Virgo S190426c: Potential host galaxies from the GLADE catalog
  30. LIGO/Virgo S190426c: INTEGRAL prompt observation
  31. Baksan Neutrino Observatory Alert 190405.62: Global MASTER-Net:LIGO/Virgo S190425z: PanSTARR OT AT2019ebq/PS19qp
  32. LIGO/Virgo S190425z: Pierre Auger Observatory follow-up
  33. LIGO/Virgo S190426c: Identification of a GW compact binary merger candidate
  34. LIGO/Virgo S190426c Global MASTER-Net observations report
  35. LIGO/Virgo S190426c: HAWC follow-up
  36. LIGO/Virgo S190425z: YAHPT Optical Observation
  37. LIGO/Virgo S190425z: Nearby Galaxies in the Updated Localization Volume
  38. LIGO/Virgo S190426c: IceCube Neutrino Search
  39. LIGO/Virgo S190425z: GROND observations of AT2019ebq/PS19qp
  40. LIGO/Virgo S190425z: Updated localization from LIGO and Virgo data
  41. LIGO/Virgo S190425z: TAROT-GRANDMA observation report
  42. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  43. LIGO/Virgo S190425z: ZTF pre-merger limits on PS1 candidates
  44. LIGO/Virgo S190425z: DCT ZTF19aarykkb spectroscopy
  45. LIGO/Virgo S190425z: CALET Observations
  46. LIGO/Virgo S190425z: KMTNet Observation
  47. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  48. LIGO/Virgo S190425z: Swope follow-up observations
  49. LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
  50. LIGO/Virgo S190425z: Liverpool Telescope spectroscopy of ZTF19aarykkb
  51. Problem with GCN Circular and status of the fix
  52. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  53. LIGO/Virgo S190425z - HCT spectroscopy
  54. LIGO/Virgo S190425z: STARE2 simultaneous L-band radio observations
  55. LIGO/Virgo S190425z: KPED Follow-Up Observations
  56. LIGO/Virgo S190425z: OVRO-LWA simultaneous low frequency radio observations of localization region
  57. LIGO/Virgo S190425z: CLU/NED Galaxies in the Localization Volume
  58. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  59. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  60. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  61. LIGO/Virgo S190425z: Xinglong/Schmidt follow-up observations
  62. LIGO/Virgo S190425z: LOAO Observation
  63. LIGO/Virgo S190425z: Palomar Gattini-IR wide-field infrared follow-up
  64. LIGO/Virgo S190425z: AGILE-GRID Observations
  65. LIGO/Virgo S190425z: Fermi GBM Observations
  66. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  67. LIGO/Virgo S190425z: SQUEAN Observation
  68. LIGO/Virgo S190425z: MMT Follow-Up Observations
  69. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  70. LIGO-Virgo S190425z: AGILE MCAL observation
  71. LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
  72. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  73. LIGO/Virgo S190425z: MAXI/GSC Observations
  74. LIGO/VIRGO S190425z: IceCube Neutrino Search
  75. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  76. LIGO/VirgoS190425z: HAWC follow-up
  77. LIGO/Virgo S190425z: SAGUARO follow-up observations
  78. LIGO/Virgo S190425z: Potential host galaxies from the GLADE catalog
  79. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  80. LIGO/Virgo S190425z: INTEGRAL prompt observation
  81. LIGO/Virgo S190425z: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo S190425z Global MASTER-Net observations report
  83. Fermi GRB190425.09 Global MASTER-Net observations report
  84. GRB 190424A: Swift-BAT refined analysis
  85. GRB 190424A: Swift detection of a burst
  86. LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
  87. GRB 190422A: Fermi GBM detection
  88. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  89. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  90. GRB 190422A: Swift-BAT refined analysis
  91. LIGO/Virgo S190421ar/G330308: ANTARES neutrino search
  92. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  93. LIGO/Virgo S190421ar: MAXI/GSC Observations
  94. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  95. Swift GRB190422.96 Global MASTER-Net observations report
  96. Fermi GRB190422.96 Global MASTER-Net observations report
  97. Fermi GRB190422.67 Global MASTER-Net observations report
  98. GRB 190422A: Swift detection of a burst
  99. LIGO/Virgo S190421ar: Fermi-GBM Observations
  100. LIGO/Virgo S190421ar Global MASTER-Net observations report

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