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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"

27305 results found.

  1. Fermi trigger No 591321287: Global MASTER-Net observations report
  2. LIGO/Virgo S190923y: MASTER OT outburst detection inside NSBH merger error-box
  3. GRB 190926A: Swift/UVOT Upper Limits
  4. GRB 190926A: Swift-XRT refined Analysis
  5. Swift GRB190926.41: Global MASTER-Net observations report
  6. GRB 190926A: Swift detection of a burst
  7. LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
  8. LIGO/Virgo S190923y: no counterpart candidates in the Swift/BAT observations
  9. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  10. LIGO/Virgo S190924h: Not observable by CALET
  11. LIGO/Virgo S190924h: no counterpart candidates in the Swift/BAT observations
  12. LIGO/Virgo S190923y: No neutrino candidates at Pierre Auger Observatory
  13. LIGO/Virgo S190924h: Upper limits from Fermi-GBM Observations
  14. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  15. LIGO/Virgo S190923y: No counterpart candidates in Fermi-LAT observations
  16. LIGO/Virgo S190924h: Global MASTER-Net observations report
  17. LIGO/Virgo S190923y: Upper limits from CALET observations.
  18. LIGO/Virgo S190923y: INTEGRAL IBIS coded-masked imaging observations of part of the localization area and further all-sky upper limits
  19. LIGO/Virgo S190923y: Upper limits from Fermi-GBM Observations
  20. GRB 190923A: BALROG localization (Fermi Trigger 590942887 / GRB 190923617)
  21. GRB 190923A: Fermi GBM Final Real-time Localization
  22. LIGO/Virgo S190923y: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S190923y: No counterpart candidates in HAWC observations
  24. LIGO/Virgo S190923y: Global MASTER-Net observations report
  25. Fermi trigger No 590899086: Global MASTER-Net observations report
  26. IceCube-190922B: Upper limits from Fermi-GBM Observations
  27. IceCube-190922A: Upper limits from Fermi-GBM Observations
  28. IceCube Alert 190922.96: Global MASTER-Net observations report
  29. Fermi trigger No 590777160: Global MASTER-Net observations report
  30. GRB 190921A: Fermi GBM Final Real-time Localization
  31. GRB 190919B: BOOTES-5/JGT and BOOTES-3/YA optical observations
  32. Baksan Neutrino Observatory Alert 190920.65: Global MASTER-Net observations report
  33. GRB 190919B: LCO Optical Afterglow Detection
  34. GRB 190919B: Swift/UVOT Upper Limits
  35. GRB 190919B: FRAM-Auger optical detection
  36. GRB 190919B: MASTER OT early detection at GROND position
  37. GRB 190919B: GROND detection of the NIR afterglow
  38. Integral GRB190919.99: Global MASTER-Net observations report
  39. Fermi trigger No 590621700: Global MASTER-Net observations report
  40. Fermi trigger No 590610007: Global MASTER-Net observations report
  41. GRB 190919A: Fermi GBM Final Real-time Localization
  42. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  43. LIGO/Virgo S190910h: No significant candidates in TAROT-GRANDMA observations
  44. Correction on name for HAWC-190916A to HAWC-190917A
  45. HAWC-190916A: Upper limits from Insight-HXMT/HE observations
  46. HAWC-190916A: Upper limits from Fermi-GBM Observations
  47. LIGO/Virgo S190915ak: No transient candidates in CALET observations
  48. HAWC-190916A: DDOTI Optical Observations
  49. Correction on the Trigger Date HAWC-190916A --> HAWC-190917A
  50. Fermi trigger No 590335819: Global MASTER-Net observations report
  51. Alert from the HAWC Burst Monitor HAWC-190917A
  52. LIGO/Virgo S190915ak: no counterpart candidates in the Swift/BAT observations
  53. LIGO/Virgo S190915ak: Upper limits from Fermi-GBM Observations
  54. LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
  55. GRB 190916A: Fermi GBM Final Real-time Localization
  56. LIGO/Virgo S190915ak: Coverage and upper limits from MAXI/GSC observations
  57. GRB 190915A: Insight-HXMT/HE detection
  58. GRB190915A: MASTER optical observation of BALROG Fermi GRB localization
  59. LIGO/Virgo S190915ak: Identification of a GW compact binary merger candidate
  60. LIGO/Virgo S190915ak: Global MASTER-Net observations report
  61. GRB 190915A: BALROG localization (Fermi Trigger 590219102 / GRB 190915240)
  62. GRB 190915A: Fermi GBM Final Real-time Localization
  63. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  64. LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
  65. GRB 190914A: Fermi GBM Final Real-time Localization
  66. LIGO/Virgo S190910h: WHT spectroscopy of Gaia19ebl, Gaia19eba, Gaia19eaz
  67. Fermi trigger No 590038994: Global MASTER-Net observations report
  68. LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
  69. LIGO/Virgo S190910d: MASTER previous detection of Gaia19eba/AT2019qam
  70. Baksan Neutrino Observatory Alert 190913.27: Global MASTER-Net observations report
  71. GRB 190913A: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo S190910h: Upper limits from CALET observations.
  73. LIGO/Virgo S190910d: No transient candidates in CALET observations.
  74. LIGO/Virgo S190910h: WHT spectroscopy of AT2019pyz/PS19fbi
  75. LIGO/Virgo S190910h and S190910d: WHT photometry of ZTF candidates
  76. LIGO/Virgo S190910h: WHT spectroscopy of ZTF19abygvmp/AT2019pzg
  77. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  78. LIGO/Virgo S190910d: No neutrino candidates at Pierre Auger Observatory
  79. LIGO/Virgo S190910h: Four additional candidates from the Zwicky Transient Facility
  80. Update to the Fermi GBM Localizations
  81. LIGO/Virgo S190910h: Candidates from the Zwicky Transient Facility
  82. LIGO/Virgo S190910d: Liverpool Telescope spectroscopy of ZTF19abyfazm
  83. LIGO/Virgo S190910d: AstroSat CZTI upper limits
  84. LIGO/Virgo S190910h: no counterpart candidates in the Swift/BAT observations
  85. LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
  86. LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
  87. LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
  88. LIGO/Virgo S190910h Global MASTER-Net observations report
  89. LIGO/Virgo S190910h: Coverage and upper limits from MAXI/GSC observations
  90. LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
  91. LIGO/Virgo S190910d: no counterpart candidates in the Swift/BAT Observations
  92. Swift Trigger 924641 is an outburst from MAXI J1807+132
  93. LIGO/Virgo S190910d: Coverage and upper limits from MAXI/GSC observations
  94. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  95. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  96. LIGO/Virgo S190910d Global MASTER-Net observations report
  97. GRB 190910A: Fermi GBM Final Real-time Localization
  98. ZTF19abvizsw/AT2019pim, search for GRB in SPI-ACS/INTEGRAL data
  99. Fermi trigger No 589561732 Global MASTER-Net observations report
  100. Fermi trigger No 589487114 Global MASTER-Net observations report

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