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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

103 results found.

  1. GRB 230307A: possibly the second highest GRB energy fluence ever identified
  2. GRB 230307A: GECAM detection of an extremely bright burst
  3. GRB 221009A: Determination of the black holes mass and spin
  4. GRB 221009A: a 397.7 GeV photon observed by Fermi-LAT at 0.4 day after the GBM trigger
  5. GRB 221009A: Fermi-LAT refined analysis
  6. GRB 211023A: OAJ Bright Afterglow Confirmation
  7. GRB 190114C: Possible host galaxy in Pan-STARRS
  8. GRB 180720B: Testing the universality of the newly born neutron star in BdHNe
  9. GRB 160509A: TLS Tautenburg Afterglow Detection
  10. GRB 150513A: request for X-ray follow up
  11. GRB 140330A: intense and persistent gamma-ray emission detected by AGILE
  12. GRB 130831A: VLT/FORS2 spectroscopic detection of a supernova
  13. GMRT radio observation of GRB 130603B
  14. GRB 130427A / SN 2013cq: Hubble Space Telescope Observations
  15. VLT observations of GRB 130427A
  16. GRB 130427A: Konkoly optical observations
  17. GRB 130427A:: BTA spectroscopic observations on May 10/11.
  18. GRB 130427A: Continued RATIR Optical and NIR Observations - Photometric Evidence for a New Component
  19. GRB 130427A: Skynet detections of a possible supernova
  20. GRB 130427A: Spectroscopic detection of the SN from the 10.4m GTC
  21. GRB 130427A: optical observations
  22. GRB 130514A: P60 Observations
  23. GRB 130427A: Tautenburg 2nd epoch: No break, no clear SN
  24. GRB 130427A: host galaxy observations
  25. GRB 130427A: Keck/LRIS Observations
  26. GRB 130427A: Ten nights of Skynet/PROMPT/GORT observations
  27. GRB 130427A: Continued RATIR Optical and NIR Observations
  28. GRB 130427A, LBT optical spectrum
  29. GRB 130427A, Watcher afterglow detection
  30. GRB 130427A: Excess optical emission consistent with an emerging supernova
  31. GRB 130427A: Amateur observations from Sweden
  32. GRB 130427A: Tautenburg afterglow observations
  33. GRB 130427A: RHESSI observations
  34. GRB 130427A: optical observations in CrAO
  35. GRB 130505A: E_iso record retraction
  36. GRB 130427A: correction to GCN 14487
  37. GRB 130505A: Largest E_iso ever measured
  38. GRB 130427A: Non-observation of VHE emission with HAWC
  39. GRB 130427A: Pan-STARRS 1 optical observations
  40. GRB 130427A: MITSuME Ishigakijima Optical Observation after 5 days
  41. GRB 130427A: Predictions about the occurrence of a supernova
  42. GRB 130427A: KAIT optical observations
  43. GRB 130427A: SARA-N optical observations
  44. GRB 130427A: VLA 20 GHz detection
  45. GRB 130427A: ABT optical observations
  46. GRB 130427A: High-energy neutrino search
  47. GRB 130427A: GMRT radio detection
  48. GRB 130427A: Continued GMG optical observations
  49. GRB 130427A: Nishi-Harima Optical Spectroscopic Observations
  50. GRB 130427A: photo-z of possible SDSS host galaxy
  51. GRB 130427A: high energy gamma-ray detection by AGILE
  52. GRB 130427A: Continued RATIR Optical and NIR Observations
  53. GRB 130427A: MITSuME Ishigakijima Optical Observation after 2 days
  54. GRB 130427A: Challis Observatory optical observations
  55. GRB 130427A: Continued Skynet/PROMPT Observations
  56. GRB 130427A: further GMG observations
  57. GRB 130427A: Fermi-LAT refined analysis
  58. GRB 130427A: SARA-N detection
  59. GRB 130427A: Continued RATIR Optical and NIR Observations
  60. GRB 130427A: CrAO RT-22 36 GHz observation
  61. GRB 130427A in the Ep,i - Eiso plane
  62. GRB 130427A: Improved Swift-XRT analysis
  63. GRB 130427A: MITSuME Okayama and Ishigakijima Optical Observation after 1 day
  64. GRB 130427A: Skynet/PROMPT Observations
  65. GRB 130427A: Nishi-Harima NIR Observations
  66. GRB 130427A: CARMA 3mm observations
  67. GRB 130427A : Xinglong TNT optical observation
  68. GRB 130427A: VLT/X-shooter redshift confirmation
  69. GRB 130427A optical time series
  70. GRB 130427A, Optical Observations
  71. GRB 130427A: Continued iTelescope T21 optical observations
  72. Konus-Wind observation of GRB 130427A
  73. GRB 130427A: Kanata/HOWPol optical imaging polarimetry
  74. GRB 130427A: Swift-XRT refined Analysis
  75. GRB 130427A: SPI-ACS/INTEGRAL observations
  76. GRB 130427A: Continued RATIR Optical and NIR Observations
  77. GRB 130427A: CARMA 85 GHz detection
  78. GRB 130427A: SNUO/SOAO/BOAO Observation
  79. GRB 130427A: VLA 5 GHz detection
  80. GRB 130427A: NOT optical photometry and redshift
  81. GRB 130427A: RAPTOR Bright Counterpart Before Swift Trigger
  82. GRB 130427A: T100 observations
  83. GRB 130427A: optical observations in CrAO
  84. GRB 130427A: Fermi GBM observation
  85. GRB 130427A: Fermi-LAT detection of a burst
  86. GRB 130427A: Swift-BAT refined analysis
  87. GRB 130427A: Zadko observatory - Gingin optical observations
  88. GRB 130427A: GMG optical observation
  89. GRB 130427A: MITSuME Okayama Optical Observation
  90. GRB 130427A: Optical Observations
  91. GRB 130427A: MAXI/GSC detection
  92. GRB 130427A: RATIR Optical and NIR Observations
  93. GRB 130427A: Weihai optical observations
  94. GRB 130427A: iTelescope T11 optical observations
  95. GRB 130427A: Continued P60 follow-up of an extremely bright optical afterglow
  96. GRB 130427A: Gemini-North redshift
  97. GRB 130427A: MITSuME Akeno Optical observation(T0+8000s~)
  98. GRB 130427A: PAIRITEL NIR Detections
  99. GRB 130427A: Faulkes Telescope North detection
  100. GRB 130427A: P60 early detection

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