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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').
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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"

3386 results found.

  1. GRB 170830A: MAXI/GSC detection
  2. LIGO/Virgo G299232: observations of the optical Transient Discovered by Swift/UVOT
  3. LIGO/Virgo G299232: COATLI Observations of MASTER OT J033744.97+723159.0
  4. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  5. LIGO/Virgo G299232: Continued observation of the transient near NGC 1343
  6. IPN Triangulation of GRB 170827B (short)
  7. LIGO/Virgo G299232 TZAC/TAROT observations
  8. GROND observations of GRB170827A
  9. GRB 170827A: ePESSTO NTT afterglow candidate
  10. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  11. GRB 170827A: Swift detection of a burst
  12. LIGO/Virgo G299232: CALET Observations
  13. LIGO/Virgo G298936: CALET Observations
  14. LIGO/Virgo G298936 TAROT/TZAC observations
  15. LIGO/Virgo G298048: LWA radio observations
  16. LIGO/Virgo G298389: CALET Observations
  17. LIGO/Virgo G298048: CALET Observations
  18. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  19. LIGO/Virgo G298048: Archival 2MASS and Spitzer non-detections of the potential LIGO EM counterpart SSS17a
  20. LIGO/Virgo G298048: SkyMapper uvgri photometry of the candidate in NGC 4933
  21. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  22. LIGO/Virgo G298048: Subaru HSC follow-up observations
  23. LIGO/Virgo G298048: Inspection of archival HST data at the position of the potential optical counterpart
  24. LIGO/Virgo G298048: REM optical/NIR observations of candidate in NGC 4993
  25. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  26. LIGO/Virgo G296853: Pierre Auger Observatory neutrino follow-up
  27. LIGO/Virgo G297595: Fermi GBM Observations
  28. GRB 170813A: Swift detection of a burst
  29. LIGO/Virgo G296853: BOOTES-1 and GTC optical observations
  30. LIGO/Virgo G296853: Insight-HXMT observations
  31. LIGO/Virgo G296853 : MAXI/GSC observations
  32. LIGO/Virgo G296853: Super-AGILE observations
  33. LIGO/Virgo G296853: no INTEGRAL data at the time of the event
  34. LIGO/Virgo G296853: Fermi-LAT search for high-energy gamma-ray counterpart
  35. LIGO/Virgo G296853: AGILE GRID observations
  36. LIGO/Virgo G296853: Swift/BAT data search
  37. LIGO/Virgo G296853: AGILE MCAL observations
  38. LIGO/Virgo G296853: Identification of a GW Binary Merger Candidate
  39. GRB 170808A: MAXI/GSC detection
  40. GRB 170728B: time correction to MASTER GCN Circular 21391
  41. Swift J181723.1-164300: Swift detection of another pulse of the new Galactic source
  42. GRB 170728B: BOOTES-2/TELMA optical detection during the extended gamma-ray phase
  43. GRB 170728B: MASTER-IAC first minute short GRB early OT detection
  44. GRB 170728B iTelescope observation
  45. GRB 170728B: Fermi GBM detection
  46. GRB 170728B: Fermi-LAT detection
  47. GRB 170728B: LT afterglow confirmation
  48. GRB 170728B: TNG optical afterglow candidate
  49. Swift triggers on a new galactic source: Swift J181723.1-164300
  50. GRB 170728A: Swift detection of a burst
  51. Fermi GBM Detection of possible burst from AXP 4U 0142+61
  52. GRB 170705A: TShAO optical observations
  53. GRB 170710B: Fermi GBM observation
  54. GRB 170629A: Fermi GBM observation
  55. GRB 170626A: MASTER-Tunka OT detection.
  56. GRB 170626A: Swift-BAT refined analysis
  57. GRB 170626A: TNG optical observations
  58. GRB 170626A: Afterglow detection from 1.5m OSN
  59. GRB 170626A: SAO RAS possible OT detection
  60. GRB 170626A: Swift-XRT refined Analysis
  61. GRB 170626A: Swift detection of a burst
  62. IPN Triangulation of GRB 170616A (short/hard)
  63. GRB 170519A: Mondy optical observations
  64. Swift Trigger 755873: MASTER Net optical observations
  65. GRB 170519A: CrAO optical observations
  66. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  67. LIGO/Virgo G268556: BSA radio observations at 110 MHz
  68. GRB 170511A CALET Gamma-Ray Burst Monitor detection
  69. GRB 170522A: Swift-XRT observations
  70. LIGO/Virgo G277583: UH88/SNIFS classification of ATLAS and PS1 transients
  71. GRB 170516A: Swift-BAT refined analysis
  72. LIGO/Virgo G284239: Konus-Wind observations
  73. LIGO/Virgo G284239: H.E.S.S. very-high energy gamma-ray follow-up
  74. LIGO/Virgo G284239: HAWC follow-up
  75. GRB 170428A CALET Gamma-Ray Burst Monitor detection
  76. Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
  77. GRB 170428A: GROND detection of the afterglow
  78. GRB 170428A: Xinglong 2.16-m upper limit and host galaxy candidate
  79. GRB 170428A: MASTER-OAFA early optical observations
  80. GRB 170419A: Swift detection of a burst
  81. Swift Trigger 748858: a possible GRB
  82. Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
  83. LIGO/Virgo G277583: CALET Observations
  84. GRB 170318A: Prompt enhanced Swift-XRT position
  85. IceCube-170312A: MASTER follow-up observations
  86. GRB 170317A: MITSuME Okayama Optical Observation
  87. LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days
  88. LIGO/Virgo G277583: ERRATUM LV GCN 20871: TAROT Calern (TCA) observations
  89. LIGO/Virgo G277583: TAROT Calern (TCA) observations
  90. LIGO/Virgo G277583: SVOM/Mini-GWAC observations of the initial skymap
  91. LIGO/Virgo G275404: Medicina radio follow-up of near-infrared
  92. Konus-Wind observation of GRB 170311B
  93. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  94. LIGO/Virgo G275697: Further Swift-XRT sources
  95. GRB 170228B CALET Gamma-Ray Burst Monitor detection
  96. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  97. GRB 170228B: POLAR Observation
  98. GRB 170228A: Fermi GBM observation
  99. GRB 170228A: Fermi-LAT detection
  100. LIGO/Virgo G275697: CALET Observations

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