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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"

2724 results found.

  1. Fermi GRB190425.09 Global MASTER-Net observations report
  2. LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
  3. LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
  4. Swift GRB190422.96 Global MASTER-Net observations report
  5. Fermi GRB190422.67 Global MASTER-Net observations report
  6. LIGO/Virgo S190421ar Global MASTER-Net observations report
  7. LIGO/VIRGO S190421ar: IceCube Neutrino Search
  8. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  9. Fermi GRB190420.98 Global MASTER-Net observations report
  10. LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
  11. Fermi GRB190419.41 Global MASTER-Net observations report
  12. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  13. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  14. GRB190404C: GROWTH-India discovery of optical counterpart
  15. GRB 140404B: MAXI/GSC detection
  16. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  17. GRB 190331A: Fermi GBM detection
  18. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  19. GRB 190324A: Swift/UVOT Observations
  20. GRB 190326A: Swift detection of a short burst
  21. GRB 190324A: Swift/UVOT afterglow candidate
  22. Swift detection of LS I +61 303
  23. Trigger 890732: Swift detection of MAXI J1631-479
  24. IceCube-190221A: MASTER Global Robotic Net optical observation
  25. Trigger 888312: Swift detection of 4U 1901+03
  26. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  27. GRB 190202A: SAO RAS optical observations
  28. GRB 190129A: MAXI/GSC detection
  29. Swift Trigger 886157: MASTER optical observation
  30. IPN Triangulation of GRB 190117A (long)
  31. GRB 190114C: UKIRT JHK observation (CORRECTIONS)
  32. GRB 190114C: Continued UKIRT JHK observation
  33. GRB 190114C: UKIRT JHK observation
  34. GRB 190114C: REM optical/NIR detection
  35. GRB 190114B: Liverpool Telescope near-IR observations
  36. CORRECTED TARGET NAME: GRB 190114C: Planned XMM-Newton observation
  37. GRB 190114C: MASTER afterglow Detection
  38. IceCube-190104A: Swift-XRT observations
  39. GRB 190106A: GMG photometry in the 2nd night
  40. GRB 190106A: Swift detection of a burst with an optical counterpart
  41. GRB 181228A: Global MASTER Net OT detection
  42. GRB 181225A: KAIT Follow-Up Observations with Upper Limit
  43. Trigger 878548: Swift detection of AX 1631.9-4752
  44. Konus-Wind observation of GRB 181212A
  45. IPN Triangulation of GRB 181212A (long)
  46. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  47. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  48. GRB 181203A: Swift detection of a burst
  49. Konus-Wind observation of GRB 181121A
  50. GRB 181125A: Swift detection of a burst
  51. GRB 181030A: MASTER Net OT detection
  52. GRB 181030A: SAO RAS optical observations
  53. IPN Triangulation of GRB 181028A (long)
  54. GRB 180728B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 554505003)
  55. GRB 181022A: Swift-XRT refined Analysis
  56. GRB 181020A: Swift/UVOT Detection
  57. GRB 181020A: Global MASTER Net OT observations
  58. GRB 181020A: VLT/X-shooter spectroscopy and redshift
  59. GRB 181020A: Swift detection of a burst with an optical counterpart
  60. GRB 181011A: Global MASTER Net optical inspection
  61. GRB 181011A: MAXI/GSC detection
  62. GRB180913A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 558557292)
  63. GRB 181008B: Global MASTER Net optical inspection
  64. GRB 180930A: Swift-XRT refined Analysis
  65. GRB 180930A: Swift detection of a burst
  66. GRB 180914B: OAJ multi-color follow-up
  67. IPN Triangulation of GRB 180914A (long)
  68. GRB 180914B: MASTER OT automatic dtection
  69. GRB 180914B: KAIT Optical Afterglow Candidate
  70. GRB 180828A: RATIR Optical and NIR Observations
  71. GRB 180828A: Swift-BAT refined analysis
  72. GRB 180828A: Swift-XRT refined Analysis
  73. GRB 180828A / Swift J1754.9-2548: Enhanced Swift-XRT position
  74. GRB 180828A: Swift detection of a GRB or possible Galactic Transient Swift J1754.9-2548
  75. GRB 180821A: BOOTES-3/YA optical observations
  76. GRB 180809A: Swift-XRT afterglow detection
  77. GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
  78. GRB 180720B: MASTER Global Net OT observations
  79. GRB 180715B: AstroSat CZTI detection
  80. FRB 180714: MASTER optical inspection of the Fast Rado Burst Transient
  81. GRB 180721A: Swift detection of a burst
  82. GRB 180720C: LT observations
  83. GRB 180718A: MASTER optical observation
  84. GRB180715B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 553369644)
  85. GRB 180718A short GRB detected by IPN and found in ground analysis of BAT data
  86. Swift Trigger 848621 is not an astrophysical event
  87. IceCube-171106A: MASTER optical observation
  88. GRB 180709A: Optical limits
  89. GRB 180703A: Swift/UVOT Upper Limits
  90. GRB 180701A: MAXI/GSC detection
  91. GRB 180626C: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 551697835)
  92. Konus-Wind observation of GRB 180626B
  93. IPN Triangulation of GRB 180626B (short)
  94. GRB 180624A: Swift-BAT refined analysis
  95. GRB 180624A: MITSuME Okayama optical upper limits
  96. Konus-Wind observation of GRB 180618A (a short GRB with extended emission)
  97. GRB 180614A: MASTER observation
  98. Konus-Wind observation of GRB 180611A
  99. GRB 180602A: MITSuME Okayama optical upper limits
  100. IPN Triangulation of GRB 180526A (long)

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