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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"

24587 results found.

  1. LIGO/Virgo G298048: Zadko Telescope 7 day observations of the OT candidate SSS17a/DLT17ck
  2. LIGO/Virgo G299232 : MAXI/GSC observations
  3. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  4. GRB 170826B: Insight-HXMT detection
  5. LIGO/Virgo G299232: WHT spectrum of MASTER OT J033744.97+723159.0
  6. LIGO/Virgo G299232/PGWB170825.55: MASTER OT J033744.97+723159.0 inside 25m isophota of the NGC1343 galaxy is reddening
  7. IPN Triangulation of GRB 170827B (short)
  8. IPN Triangulation of GRB 170826A (short)
  9. LIGO/Virgo G298936: HAWC follow-up
  10. LIGO/Virgo G299232 TZAC/TAROT observations
  11. GROND observations of GRB170827A
  12. LIGO/Virgo G299232: OVRO-LWA simultaneous low frequency radio observations of localization region
  13. GRB 170827A, Swift-BAT refined analysis
  14. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  15. GRB 170826B: Fermi GBM detection
  16. LIGO/Virgo G299232: CALET Observations
  17. GRB 170826A: Fermi GBM detection
  18. LIGO/Virgo G298936: Astrosat CZTI upper limits
  19. LIGO/Virgo G299232: XRT Rank 2 source is not real
  20. LIGO/Virgo G299232: Astrosat CZTI upper limits
  21. LIGO/VIRGO G299232: Fermi GBM Observations
  22. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  23. LIGO/Virgo G298389: HAWC follow-up
  24. LIGO/Virgo G298048: uGMRT Follow-up of SSS17a at 400 MHz and 1.4 GHz
  25. LIGO/Virgo G299232: Nearby Galaxies in the Localization Volume
  26. LIGO/Virgo G298936: CALET Observations
  27. GRB 170820A CALET Gamma-Ray Burst Monitor detection
  28. LIGO/Virgo G299232: Swift/BAT data search
  29. LIGO/Virgo G299232: AGILE GRID observations
  30. LIGO/Virgo G299232: AGILE MCAL detection of a short gamma-ray candidate
  31. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  32. LIGO/Virgo G299232: COINCIDENT IceCube neutrino observation UPDATE
  33. LIGO/Virgo G299232 ANTARES search
  34. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  35. LIGO/Virgo G299232: FOUND COINCIDENT IceCube neutrino observation
  36. LIGO/Virgo G299232: Identification of a GW Compact Binary Coalescence Candidate
  37. LIGO/Virgo G298936 TAROT/TZAC observations
  38. LIGO/Virgo G298936 : MAXI/GSC observations
  39. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  40. LIGO/Virgo G298048: Pierre Auger Observatory neutrino follow-up
  41. LIGO/Virgo G298048: HAWC follow-up
  42. Konus-Wind observation of GRB 170822A
  43. GRB 170823A: Swift-BAT refined analysis
  44. LIGO/Virgo G298936: GWFUNC/CNEOST optical observations and an optical transient
  45. LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
  46. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  47. LIGO/Virgo G298048: Results of the ASKAP search for fast radio bursts
  48. LIGO/Virgo G298048: ATCA follow-up of SSS17a in NGC 4993
  49. LIGO/Virgo G298389: CALET Observations
  50. LIGO/Virgo G298936 : Fermi-LAT search for a high-energy gamma-ray counterpart
  51. GRB 170823A: Swift detection of a burst
  52. LIGO/Virgo G298936: Swift/BAT data search
  53. LIGO/VIRGO G298936: Fermi GBM Observations
  54. LIGO/Virgo G298936: AGILE GRID observations
  55. LIGO/Virgo G298936: Updated localization from gravitational-wave data
  56. LIGO/Virgo G298936: AGILE MCAL observations
  57. LIGO/Virgo G298936 ANTARES search
  58. LIGO/Virgo G298936: INTEGRAL was inactive at the time of the event
  59. LIGO/Virgo G298936: IceCube neutrino observations
  60. LIGO/Virgo G298936: Identification of a GW Binary Black Hole Candidate
  61. GRB 170822A: MITSuME Akeno Optical Observation
  62. GRB 170822A: Swift-BAT refined analysis
  63. LIGO/Virgo G298048: Chandra X-ray observations
  64. LIGO/Virgo G298048: Global properties and star-formation rate of NGC 4993
  65. LIGO/Virgo G298048: CALET Observations
  66. LIGO/Virgo G298048: MWA Observations of Error Region
  67. LIGO/Virgo G298048: Continued monitoring of the optical counterpart candidate
  68. LIGO/Virgo G298048 ANTARES search (2)
  69. Konus-Wind observation of GRB 170816A
  70. LIGO/Virgo G298389: Swift/BAT data search
  71. LIGO/Virgo G298048: TOROS optical counterpart search (continuation)
  72. LIGO/Virgo G298048: TOROS optical counterpart search
  73. LIGO/Virgo G298048: optical observations of CHILESCOPE observatory
  74. LIGO/Virgo G298389 : Fermi-LAT search for a high-energy gamma-ray counterpart
  75. LIGO/Virgo G298048: Possible X-ray detection with Swift
  76. LIGO/Virgo G298389: INTEGRAL search for a prompt gamma-ray counterpart
  77. LIGO/Virgo G298389: Fermi GBM Upper Limits
  78. LIGO/Virgo G298389: AGILE MCAL observations
  79. LIGO/Virgo G298389: AGILE GRID observations
  80. LIGO/Virgo G298389: IceCube neutrino observations
  81. LIGO/Virgo G298389 ANTARES search
  82. LIGO/Virgo G298389: Identification of a GW Burst Candidate
  83. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations
  84. LIGO/Virgo G298048: VLT linear polarimetry
  85. GRB 170817B: Insight-HXMT observation
  86. LIGO/Virgo G298048: Further VLA Observations
  87. LIGO/Virgo G298048: MASTER photometry of the SSS17a in NGC 4993
  88. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  89. LIGO/Virgo G298048: Rapid Evolution of Possible Counterpart
  90. LIGO/VIRGO G298048: Expansion Velocity of SSS17a Consistent With Relativistic Merger Ejecta
  91. GRB 170818A: Fermi GBM detection
  92. LIGO/Virgo G298048: New MASTER observations of the OT in NGC 4993
  93. LIGO/Virgo G298048: Correction to Swope photometry announced in LVC GCN 21529
  94. LIGO/Virgo G298048: Moderate dimming or no brightening of the optical counterpart candidate?
  95. LIGO/Virgo G298048: AGILE-GRID analysis of the potential counterpart field
  96. LIGO/Virgo G298048: ASKAP search for fast radio bursts
  97. LIGO/Virgo G298048: ATCA detection of a radio source coincident with NGC 4993
  98. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  99. LIGO/Virgo G298048: Likelihood of SSS17a Being an Unrelated Extragalactic Transient in NGC 4993
  100. LIGO/Virgo G298048, Fermi GBM trigger 524666471/170817.529: MAXI/GSC observations

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