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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').
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.

Advanced Search Examples (click to copy):

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

3870 results found.

  1. GRB 081029, SMARTS optical/IR afterglow observations
  2. GRB 081029: Redshift Confirmation from Gemini-South
  3. GRB 081029: REM observations
  4. GRB 081029: UVES/VLT Absorption Redshift
  5. GRB 081028: Swift-XRT refined analysis
  6. GRB 081024: Swift detection of a burst
  7. GRB 081012, Swift-BAT refined analysis
  8. GRB081006: Fermi GBM detection
  9. Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
  10. GRB 081003B: Swift-XRT upper limit
  11. GRB 081003A: OSN optical observations
  12. GRB 081003A: Swift-XRT Team position and analysis
  13. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  14. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  15. Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
  16. Trigger 330353: Swift detection of a Galactic short soft burst
  17. GRB 080928: VLT redshift
  18. GRB080928: Gemini-South Absorption Redshift
  19. GRB 080928: GROND DETECTION
  20. GRB 080925: Fermi GBM Detection
  21. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  22. GRB 080915B, Swift-BAT refined analysis
  23. SGR 0501+4516 : P200 i-band observations
  24. GRB 080905C: Fermi GBM detection
  25. SGR J0501+4516: radio pulsar searches with GBT and WSRT
  26. Swift Trigger 324122 is again known source Swift J1842.5-1124
  27. GRB 080906: Swift detection of a burst with optical afterglow
  28. Recent VLA non-detection of SGR 0501+4516
  29. SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
  30. SGR 0501+4516: preliminary results of the first XMM-Newton observation
  31. nIR observations of SGR 0501+4516
  32. INTEGRAL ToO observation of SGR0501+4516
  33. SGR 0501+4516: Confirmation of the NIR counterpart
  34. SGR 0501+4516: Detection of possible optical counterpart
  35. SGR 0501+4516: WHT observations of the possible near-infrared counterpart
  36. VLA non-detection of SGR 0501+4516
  37. Radio Detection of SGR 0501+4516: Retraction
  38. SGR 0501+4516: XMM-Newton monitoring schedule
  39. SGR 0501+4516: Decline in Activity
  40. SGR 0501+4516: Proximity to supernova remnant HB9
  41. Enhanced Swift-XRT position of SGR 0501+4516
  42. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  43. SGR 0501+4516: Swift XRT measure of the spin period
  44. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  45. Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
  46. Suzaku ToO Observation of SGR 0501+4516
  47. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  48. Konus-Wind observations of new SGR 0501+4516
  49. INTEGRAL ToO Observation of SGR0501+4516
  50. Radio Detection of SGR 0501+4516
  51. SGR 0501+4516: MDM Optical Observations
  52. SGR 0501+4516: Astrotel-Caucasus optical observations
  53. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  54. SGR 0501+4516: WSRT Radio Observations
  55. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  56. SGR 0501+4516: optical observations
  57. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  58. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  59. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  60. Third event from SGR 0501+4516
  61. GRB 080822 (SGR 0501+4516): archival optical observations
  62. New Soft Gamma Repeater 0501+4516 was GRB 080822
  63. GRB 080727B: Late VLT imaging
  64. Trigger 317393: Swift detection of a possible GRB
  65. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  66. GRB 080710, Swift-BAT refined analysis
  67. GRB 080710: Swift detection of a burst
  68. GRB 080707: Swift detection of a burst
  69. GRB 080702B : Burst detected in BAT during Swift slew
  70. GRB 080701: Swift detection of a burst
  71. GRB 080613B: Swift detection of a burst
  72. GRB 080604: Swift detection of a burst with an optical afterglow
  73. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  74. Konus-Wind observation of reactivation of SGR 1627-41
  75. Reactivation of SGR 1627-41
  76. GRB 080515: KPNO 4m NIR afterglow detection
  77. GRB 080506: NAYUTA Optical Observation
  78. GRB080430: Optical observation in AsU CAS Ondrejov & Brno
  79. GRB 080426: Swift detection of a possibly short burst
  80. GRB 080413A: MOA-II optical afterglow observations
  81. GRB 080330, SMARTS optical/IR afterglow observations
  82. GRB 080319A: UVOT Observations
  83. GRB 080319C: Swift-XRT Team Refined Analysis
  84. GRB 080319C: Swift detection of a burst with an optical afterglow
  85. GRB080310: Super-LOTIS suggestion of brightening
  86. GRB080307, optical upper limit
  87. GRB 080307: retraction of UVOT candidate
  88. GRB 080303A: ROTSE-III Optical Limits
  89. GRB080229: Possible optical afterglow
  90. UVOT analysis for GRB080229
  91. GRB 080218: Swift detection of a burst
  92. GRB 080207, Swift-BAT refined analysis
  93. GRB 080207, Swift-BAT refined analysis
  94. GRB 080129: Swift-XRT refined analysis
  95. GRB 080129: Gemini-South Imaging Observations
  96. Konus-Wind observation of GRB 080122
  97. GRB 080121: Swift-BAT detection of a very weak, short burst
  98. IPN triangulation of very bright GRB 071125
  99. Disregard the "GRB 071126" position
  100. GRB 071118: Swift detection of a burst

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