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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.

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

5556 results found.

  1. GRB 171102B: MITSuME Akeno optical upper limits
  2. IPN Triangulation of GRB 171022A
  3. GRB 171011A: Swift-BAT refined analysis
  4. IPN Triangulation of GRB 171011B (long/very bright)
  5. GRB 171011A: MASTER-SAAO optical observations
  6. GRB 171011A: Swift detection of a burst
  7. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  8. GRB 171003A: LT early optical observations
  9. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  10. LIGO/VIRGO G298048: Further MeerKAT observations of SSS17a
  11. IceCube-170922A: Swift-XRT observations
  12. IPN Triangulation of GRB 170921B
  13. LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
  14. LIGO/Virgo G297595: NIR Observations following GW170814
  15. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  16. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  17. LIGO/Virgo G299232: Swift-XRT sources
  18. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  19. LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
  20. LIGO/Virgo G299232: LOFAR follow-up
  21. GRB 170903A: UAFO /ISON optical upper limit
  22. GRB 170903A: MITSuME Okayama upper limits
  23. GRB 170903A: Nanshan optical upper limit
  24. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  25. GRB 170830A: Fermi GBM observation
  26. GRB 170830A: Astrosat CZTI detection
  27. GRB 170830A: MAXI/GSC detection
  28. LIGO/Virgo G299232: Liverpool Telescope observations
  29. LIGO/Virgo G299232: COATLI Observations of MASTER OT J033744.97+723159.0
  30. LIGO/Virgo G299232 : MAXI/GSC observations
  31. IPN Triangulation of GRB 170826A (short)
  32. LIGO/Virgo G299232 TZAC/TAROT observations
  33. LIGO/Virgo G298936 TAROT/TZAC observations
  34. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  35. LIGO/Virgo G298936: GWFUNC/CNEOST optical observations and an optical transient
  36. GRB 170823A: Swift detection of a burst
  37. LIGO/Virgo G298048: ATCA 8.5 GHz observations of galaxies in the localisation volume
  38. LIGO/Virgo G298048: TOROS optical counterpart search
  39. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  40. GRB 170818A: Fermi GBM detection
  41. LIGO/Virgo G298048: Subaru HSC follow-up observations
  42. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume
  43. LIGO/Virgo G297595: Swift-XRT sources
  44. LIGO/Virgo G297595: MASTER MASTER Bright PSN detection in error-box
  45. LIGO/Virgo G297595: INAF VST-ESO PARANAL observations
  46. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  47. LIGO/Virgo G297595: REM optical/NIR observations
  48. GRB 170810A: VLA Detection
  49. LIGO/Virgo G296853: Liverpool Telescope classification of MASTER OT J013646.48-140323.5
  50. GRB 170810A: Swift/UVOT Detection
  51. GRB 170810A: Swift detection of a burst with a bright optical counterpart
  52. GRB 170808A: MAXI/GSC detection
  53. GRB 170807A: Swift detection of a burst
  54. GRB 170804A: Swift detection of a burst with optical counterpart
  55. Swift Trigger 765783 is not an astrophysical event.
  56. GRB 170728B: time correction to MASTER GCN Circular 21391
  57. Konus-Wind observation of GRB 170728B
  58. GRB 170726A: AstroSat CZTI detection
  59. GRB 170728B: BOOTES-2/TELMA optical detection during the extended gamma-ray phase
  60. GRB 170728B iTelescope observation
  61. GRB 170728A: Swift/UVOT Detection
  62. GRB 170728B: Fermi GBM detection
  63. GRB 170728B: Swift detection of a short burst
  64. GRB 170714A: TNG NIR observations
  65. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  66. GRB 170712A: AstroSat CZTI detection
  67. GRB 170711A: ISON/Terskol and AbAO optical observations
  68. GRB 170711A: Prompt enhanced Swift-XRT position
  69. Correction to GCN Circular 21305: Trigger 760835: Swift misidentification of GRS1716-249
  70. Trigger 760835: Swift misidentification of GRS1716-249
  71. GRB 170705A: MASTER-OAFA early OT observations
  72. LIGO/Virgo G288732: Pan-STARRS coverage of the Fermi/LAT candidate position
  73. GRB 170610A: MAXI/GSC detection
  74. LIGO/Virgo G288732: Swift-XRT follow up of the putative LAT counterpart
  75. LIGO/Virgo G288732:SVOM/Mini-GWAC observations of the initial skymap
  76. GRB 170607A: MASTER-Tavrida early OT observations
  77. GRB 170531A: MASTER Net job
  78. GROND observations of GRB 170531B
  79. GRB 170531B: Redshift from GTC/OSIRIS
  80. GRB 170524B: Swift-UVOT/XRT Confirmation of Afterglow
  81. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  82. LIGO/Virgo G268556/GW170104: Konus-Wind observations
  83. GRB 170524B: Swift-XRT observations
  84. GRB 170522A: LCO McDonald observations
  85. GRB 170519A: MITSuME Akeno Optical Observation
  86. GRB 170519A: MITSuME Okayama Optical Observation
  87. LIGO/Virgo G277583: UH88/SNIFS classification of ATLAS and PS1 transients
  88. LIGO/Virgo G275404 and G275659: SkyMapper Follow-up Observations
  89. LIGO/Virgo G284239:SVOM/Mini-GWAC observations of the initial skymap
  90. LIGO/Virgo G284239: MASTER automatic follow up and synchronous observations
  91. GRB 170428A: TNG optical observations
  92. GRB 170428A: Swift detection of a short burst
  93. Swift Trigger 748858: AbAO and TSHAO optical observations
  94. GRB 170317A: SAO RAS optical observations
  95. Trigger 745966: Swift detection of 4U1850-03
  96. GRB 170325A: optical observations, possible OT/host detection
  97. IceCube-170321A: Konus-Wind upper limits
  98. Fermi-LAT Gamma-ray Observations of IceCube-170321
  99. DOAO 1m telescope V, R, I observation of GRB 170317A
  100. IceCube-170321A: Swift-XRT observations

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