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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"

2623 results found.

  1. GRB 170531B: MASTER Net optical counterpart refind position and magnitude
  2. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  3. LIGO/Virgo G268556: BSA radio observations at 110 MHz
  4. GRB 170524A: Swift detection of a burst (or possible new SGR)
  5. LIGO/Virgo G277583: UH88/SNIFS classification of ATLAS and PS1 transients
  6. GRB 170510A: Global MASTER Net possible OT observations
  7. GRB 170510A: LCO possible counterpart
  8. LIGO/Virgo G284239: Fermi-LAT search for a high-energy gamma-ray counterpart
  9. LIGO/Virgo G284239: INTEGRAL search for a prompt gamma-ray counterpart
  10. Swift Trigger 748858: 15 GHz upper limits from AMI
  11. GRB 170428A: TNG optical observations
  12. Swift Trigger 748858: MASTER-OAFA early optical observations
  13. Swift Trigger 748858: a possible GRB
  14. Konus-Wind observation of GRB 170409A
  15. GRB 170325A: optical observations, possible OT/host detection
  16. Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
  17. LIGO/Virgo G275697: AMI Large Array Search for a Radio Afterglow
  18. IceCube-170321A - IceCube observation of a high-energy neutrino candidate event
  19. IceCube-170312A: MASTER follow-up observations
  20. LIGO/Virgo G277583: ATLAS17cck - a fast declining transient
  21. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  22. LIGO/Virgo G275404: Medicina radio follow-up of near-infrared
  23. LIGO/Virgo G270580: optical observations and classification of PS and MASTER sources
  24. SN MASTER OT J042250.16-820415.4 is the possible optical counterpart of the gravitational waves event LIGO/Virgo G274296
  25. GRB170306A: SALT observations
  26. LIGO/Virgo G275404 and AGL J1914+1043: INTEGRAL follow-up
  27. Swift Trigger 741528: a possible GRB
  28. LIGO/Virgo G275697: Additional iPTF Optical Transient Candidates
  29. LIGO/Virgo G274296 and G275404 : MAXI/GSC observations
  30. LIGO/Virgo G275697: Fermi-LAT search for a high-energy gamma-ray counterpart
  31. LIGO/Virgo G275697: INTEGRAL search for a prompt gamma-ray counterpart
  32. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  33. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  34. LIGO/Virgo G275404: AGILE-GRID detection of a possible gamma-ray transient
  35. LIGO/Virgo G274296: MASTER new bright possible SN detection and inspection dinamic
  36. LIGO/Virgo G274296: Fermi-LAT search for a high-energy gamma-ray counterpart
  37. LIGO/Virgo G274296: Pan-STARRS imaging and discovery of 70 transients
  38. LIGO/Virgo G274296: INTEGRAL search for a prompt gamma-ray counterpart
  39. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  40. GRB 170208B: GROND observations
  41. GRB 170205A: Swift-BAT refined analysis
  42. LIGO/Virgo G268556: FLOYDS Spectrum of iPTF17cf/PS17fr Favors an AGN Classification
  43. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  44. GRB 170121B: AbAO optical observations
  45. GRB 170121B: MASTER early optical observations of the Swift possible XT
  46. GRB 170121B: Swift-XRT and UVOT observations
  47. LIGO/Virgo G270580: Fermi-LAT search for a high-energy gamma-ray counterpart
  48. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  49. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  50. Swift Trigger #733426: possible detection of a burst or transient
  51. LIGO/Virgo G268556: spectra of two nuclear transients PS17fr and PS17er
  52. LIGO/Virgo G268556: Gemini spectra of Pan-STARRS1 transients
  53. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF17bv and iPTF17ck
  54. GRB170105A: AstroSat CZTI localisation
  55. LIGO/Virgo G268556: Palomar 200-inch detects ATLAS17aeu, possible afterglow of GRB070105A?
  56. LIGO/Virgo G268556/GW170104: Global MASTER Net observations and first OT detection
  57. LIGO/Virgo G268556: Fermi-LAT search for high-energy gamma-ray counterpart
  58. LIGO/Virgo G268556: Mini-MegaTORTORA follow-up observations
  59. LIGO/Virgo G268556: INTEGRAL search of temporally coincident prompt hard X-ray emission
  60. GMRT radio detection of GRB 161219B
  61. Swift Trigger 728268: a possible GRB
  62. Swift Trigger 728094: a possible GRB
  63. GRB 161218A: Swift-BAT refined analysis
  64. GRB 161214B: Swift/UVOT Observations
  65. GRB 161214B: NOT optical observations, possible counterpart
  66. IceCube-161210: IceCube observation of a high-energy neutrino candidate event
  67. GRB 161129A: TSHAO optical observations / possible afterglow+host galaxy
  68. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  69. GRB 161104A: Magellan imaging and spectroscopy
  70. GRB 161106A: CALET Gamma-Ray Burst Monitor detection
  71. IceCube-161103: IceCube observation of a very-high-energy neutrino
  72. Radio upper limit on the GRB 161011A with the GMRT
  73. GRB161004A: Further analysis of the burst nature
  74. GRB 161010A: Swift/UVOT Possible Detection
  75. GRB 161007A: Swift/UVOT Upper Limits
  76. GRB 161004A: Swift-BAT refined analysis
  77. GRB 161004A: Swift detection of a burst with a possible optical counterpart
  78. Possible radio detection of GRB 160910A with the GMRT
  79. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  80. GRB 160925A: Optical spectroscopy of MASTER optical transient
  81. GRB 160816A: Possible radio afterglow detection at 15 GHz with AMI
  82. IceCube HESE 160814: MASTER OT J130845.02-323254.9 as the possible source of the high energy neutrino
  83. GRB 160816A, the review of the sky area in plate archives
  84. GRB 160825A: not localized by Swift
  85. GRB 160824A: Swift/UVOT Possible Afterglow Detection
  86. Possible radio detection of GRB160703A with the GMRT
  87. Possible radio detection of GRB160623A with the GMRT
  88. GRB 160821A: Swift-BAT refined analysis
  89. GRB 160816A: MASTER inspection
  90. IceCube 160806A EHE Neutrino Candidate Event
  91. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  92. GRB160804A: MASTER-SAAO observation
  93. Global MASTER net follow up of IceCube-160731A
  94. Swift Trigger 704327: KAIT Optical Observations
  95. Swift Trigger 704444 is probably not an astrophysical event.
  96. Swift Trigger 704327: MASTER syncronous optical observations
  97. Swift Trigger 704327: a possible GRB
  98. GRB 160712A: Swift/UVOT Upper Limits
  99. SGR 1935+2154: CALET Gamma-Ray Burst Monitor detections
  100. GRB 160705B: Swift-BAT refined analysis

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