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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').

92 results found.

  1. Fermi trigger No 729703985: Global MASTER-Net observations report
  2. Swift GRB231214.85: Global MASTER-Net observations report
  3. GRB 231020B: AstroSat CZTI detection
  4. GRB 230728A: Swift/UVOT Upper Limits
  5. LIGO/Virgo S230608as: Global MASTER-Net observations report
  6. GRB 230405B: Swift/UVOT Upper Limits
  7. GRB 230204A: Swift/UVOT Upper Limits
  8. Swift GRB221226.95: Global MASTER-Net observations report
  9. GRB 220803A: AstroSat CZTI detection
  10. GRB 220715B: Swift/UVOT Upper Limits
  11. Fermi GRB 211219B: Global MASTER-Net observations report
  12. Swift GRB210807.78: Global MASTER-Net observations report
  13. Fermi GRB 210606A: Global MASTER-Net observations report
  14. GRB 210517A: Swift/UVOT Upper Limits
  15. GRB 200922A: chance superposition between optical afterglow and archival star
  16. GRB 200906A: Swift/UVOT Upper Limits
  17. Improved IPN error box for GRB 200415A (consistent with the Sculptor Galaxy)
  18. Swift GRB200306.01: Global MASTER-Net observations report
  19. GRB 200216B: Swift/UVOT Upper Limits
  20. Swift GRB191227.07: Global MASTER-Net observations report
  21. GRB 191024A: Swift/UVOT Upper Limits
  22. LIGO/Virgo S190425z: Swift UVOT - no new sources identified, and a summary of the Swift UVOT processing of GW triggers.
  23. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  24. Swift GRB190427.19 Global MASTER-Net observations report
  25. LIGO/Virgo S190421ar Global MASTER-Net observations report
  26. GRB 181022A: Swift/UVOT Upper Limits
  27. GRB 180824A: MASTER inspection IPN short GRB error box
  28. GRB 180620A: Swift-XRT refined Analysis
  29. GRB 180331A: Swift/UVOT Upper Limits
  30. GRB 180329B: Swift/UVOT Detection
  31. Trigger 813449: Swift detection of large burst from XTE J1701-407
  32. GRB 171216A: Swift/UVOT Upper Limits
  33. GRB 171027A: Swift-XRT refined Analysis
  34. Konus-Wind observation of GRB 170906A
  35. GRB 170419A: Swift/UVOT Upper Limits
  36. GRB 161113A: Swift/UVOT Upper Limits
  37. GRB 161105A: Swift/UVOT Upper Limits
  38. GRB 161001A, Swift-BAT refined analysis (likely a short GRB)
  39. GRB 160815A: Swift/UVOT Detection
  40. Swift-BAT trigger 686845 was due to noise near a known source
  41. GRB 160325A: Further Swift/UVOT Observations
  42. GRB 151228B: Swift/UVOT Detection
  43. GRB 150819A: Swift/UVOT Upper Limits
  44. Swift trigger 637807 is probably not an astrophysical source
  45. GRB 150323C, Swift-BAT refined analysis
  46. GRB 150222A: Swift/UVOT Upper Limits
  47. Konus-Wind observation of GRB 141202A
  48. GRB 131002B: Swift/UVOT Upper Limits
  49. GRB 130925A: Swift/UVOT Upper Limits
  50. GRB 130907A: MASTER refined analysis
  51. GRB 130831B: Swift/UVOT Upper Limits
  52. GRB 130715A: Suzaku WAM observation of the prompt emission
  53. Trigger 538084: Swift detection of XTE J1739-302
  54. GRB 120624B Suzaku WAM observation of the prompt emission
  55. GRB 120324A: Swift/UVOT Upper Limits
  56. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  57. IBAS Alert n. 6057 is not due to a GRB
  58. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  59. GRB 100606A: Swift/UVOT Upper Limits
  60. IBAS Alert 5992 is not a GRB, but XTE J1855-026
  61. GRB 100213A: Swift XRT refined analysis
  62. Swift/BAT Detects an Outburst from XTE J1901+014
  63. Swift Trigger #382159 is due to XTE J1752-223
  64. Swift-BAT trigger 373691 is a galactic bulge transient
  65. GRB 091010: RXTE detection
  66. GRB 090516: Swift/UVOT Observations
  67. GRB 081109A: Possible Swift-UVOT detection
  68. GRB 081109: Swift/UVOT upper limits
  69. GRB 080905B: Refined UVOT Analysis
  70. Swift detection of XTE J1701-407
  71. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  72. GRB 080603B: Swift-XRT refined analysis
  73. A giant outburst from Cygnus X-1 detected by Konus-Wind and Suzaku-WAM
  74. Swift/UVOT observations of GRB070805
  75. GRB 070714A: Swift/UVOT Upper limits
  76. GRB 070309: Swift/UVOT Upper Limits
  77. GRB 061028: Swift/UVOT Observations
  78. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  79. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  80. IPN detection of continued activity from SGR1806-20
  81. Detection of activity from SGR 1900+14 with the RXTE/PCA
  82. RXTE Observations of SGR 1900+14
  83. The X-ray Flash 011030 ('GRB 011030')
  84. SGR 1900+14 : RXTE observations
  85. Further Optical Observations of GRB 010324
  86. Optical Observations of GRB 010324
  87. IPN TRIANGULATION OF GRB010115
  88. GCN resumes full operations
  89. Chandra observation of the X-ray afterglow of GRB991216
  90. GRB 990506: Limits on the possible optical transient
  91. GRB990308 (Trig. 7457), optical observations
  92. GRB 980703: BATSE Observations

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