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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"

43936 results found.

  1. GRB 170330A: Swift detection of a burst
  2. GRB 170329A: Fermi GBM detection
  3. GRB 170329A: Fermi-LAT detection
  4. GRB 170325B: POLAR Observation
  5. GRB 170325A: Fermi GBM observation
  6. LIGO/Virgo G277583: Konus-Wind observations
  7. GRB 170325A, Swift-BAT detection of a short GRB
  8. INTEGRAL pointed follow-up of IceCube-170321A
  9. LIGO/Virgo G277583: Fermi GBM Observations
  10. Konus-Wind observation of GRB 170320A
  11. GRB 170320A: POLAR Observation
  12. LIGO/Virgo G277583: INTEGRAL search for an X-ray and gamma-ray counterpart
  13. Fermi GBM Observation of IceCube-170321A
  14. LIGO/Virgo G275697: AMI Large Array Search for a Radio Afterglow
  15. Fermi GBM trigger 511851891/170322212 is not a GRB
  16. IceCube-170321A - IceCube observation of a high-energy neutrino candidate event
  17. INTEGRAL SPI-ACS observation of AMON IceCube EHE 80305071 129307
  18. IPN Triangulation of GRB 170320A (long/intense)
  19. Search for counterpart to IceCube-170321A with ANTARES
  20. GRB 170318A: KAIT Optical Upper Limit
  21. GRB 170317A: Mondy optical observations
  22. GRB 170318B: Swift-BAT refined analysis
  23. GRB 170317A: POLAR observation
  24. GRB 170318B: RATIR Optical and NIR Observations
  25. GRB 170317A: RATIR Optical and NIR Observations
  26. GRB 170318B: Swift/UVOT Upper Limits
  27. GRB 170318B: Swift-XRT refined Analysis
  28. GRB 170318A: Swift-XRT refined Analysis
  29. LIGO/Virgo G277583: CALET Observations
  30. GRB 170318A: RATIR Optical and NIR Observations
  31. GRB 170318A: Swift/UVOT Upper Limits
  32. GRB 170318B: Fermi GBM observation
  33. GRB 170318A: Swift-BAT refined analysis
  34. GRB 170317A: RATIR Optical and NIR Observations
  35. GRB 170318B: Enhanced Swift-XRT position
  36. GRB 170318B: Prompt enhanced Swift-XRT position
  37. GRB 170318B: Swift detection of a burst
  38. GRB 170318A: Enhanced Swift-XRT position
  39. GRB 170315A: POLAR observation
  40. GRB 170318A: Prompt enhanced Swift-XRT position
  41. GRB 170318A: Swift detection of a burst
  42. IceCube-170312A: MASTER follow-up observations
  43. LIGO/Virgo G277583: Asiago spectroscopic classification of ATLAS17byo and ATLAS17cgg
  44. GRB 170317A: LCO FTN observations
  45. LIGO/Virgo G277583 : MAXI/GSC observations
  46. GRB 170317A: Swift-BAT refined analysis
  47. LIGO/Virgo G277583: AstroSat CZTI upper limits
  48. GRB 170317A: Swift/UVOT Detection
  49. GRB 170317A: Mondy optical observations
  50. GRB 170317A: MITSuME Okayama Ks-band upper-limit
  51. GRB 170317A: Swift-XRT refined Analysis
  52. IceCube-170312A: Swift-XRT observations
  53. GRB 170317A: GMG observation
  54. GRB 170317A: Enhanced Swift-XRT position
  55. GRB 170317A: ISON-Ussuriysk aferglow confirmation
  56. GRB 170317A: Swift detection of a burst with an optical counterpart
  57. LIGO/Virgo G275697: Swift-XRT source 23 no longer fading
  58. LIGO/Virgo G277583: Swift/BAT data search
  59. LIGO/Virgo G277583: Discovery Channel Telescope Follow-Up of ATLAS17cck
  60. LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days
  61. GRB 170307A: 15 GHz upper limit from AMI
  62. LIGO/Virgo G277583: ATLAS17cck is likely a minor planet
  63. LIGO/Virgo G277583: GROND follow up of ATLAS17cck
  64. LIGO/Virgo G277583: ATLAS17cck - a fast declining transient
  65. LIGO/Virgo G275697: DLT40 follow-up observation
  66. LIGO/Virgo G274296: DLT40 follow-up observation
  67. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  68. LIGO/Virgo G277583: ERRATUM LV GCN 20871: TAROT Calern (TCA) observations
  69. GRB 170311B: AstroSat CZTI detection
  70. LIGO/Virgo G277583: TAROT Calern (TCA) observations
  71. LIGO/Virgo G277583: SVOM/Mini-GWAC observations of the initial skymap
  72. LIGO/Virgo G275404: Medicina radio follow-up of near-infrared
  73. Fermi GBM trigger 510642159/170308210 is not a GRB
  74. LIGO/Virgo G277583: INTEGRAL was inactive at the time of the event
  75. LIGO/Virgo G277583 ANTARES search
  76. Konus-Wind observation of GRB 170311B
  77. LIGO/Virgo G277583: AGILE GRID observations
  78. LIGO/Virgo G277583: AGILE MCAL observations
  79. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  80. LIGO/Virgo G277583: IceCube neutrino observations
  81. LIGO/Virgo G277583: Identification of a GW Burst Candidate
  82. IPN Triangulation of GRB 170311B (long/very intense)
  83. GRB 170311A: VLT observations
  84. IceCube-170312A - IceCube update on a high-energy neutrino candidate event
  85. INTEGRAL observation of IceCube HESE 65274589 129281
  86. GRB 170311A: Swift-BAT refined analysis
  87. LIGO/Virgo G275697: GRAWITA NOT optical observations of Swift/XRT Source 23
  88. GRB 170311A: Swift-XRT refined Analysis
  89. GRB 170311A: Enhanced Swift-XRT position
  90. SN MASTER OT J042250.16-820415.4 is the possible optical counterpart of the gravitational waves event LIGO/Virgo G274296
  91. GRB 170311A: GROND upper limits
  92. GRB 170311A: MASTER-OAFA early optical observations
  93. GRB 170311A: Swift detection of a burst
  94. GRB 170309A: POLAR Observation
  95. GRB170306A: SALT observations
  96. GRB 170306A: GROND afterglow detection
  97. LIGO/Virgo G275404: Swift-XRT observations of sources in the AGILE error region
  98. LIGO/Virgo G275697: Swift-XRT source 23 is fading
  99. LIGO/Virgo G275404: Updated localization from LIGO data
  100. GRB 170306B: POLAR observation

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