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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

19661 results found.

  1. GRB 261017A: SAO RAS optical upper limit
  2. GRB 261017A: COLIBRÍ optical upper limit
  3. Konus-Wind detection of GRB 261017A
  4. GRB 261017A: Possible Swift/UVOT Detection
  5. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  6. GRB 261017A: R-band upper limit with the 1.3-m DFOT
  7. GRB 261017A: Swift-BAT refined analysis
  8. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  9. GRB 261017A : MITSuME Akeno optical upper limits
  10. GRB 261017A: Swift-XRT refined Analysis
  11. GRB 261017A: Nanshan/NEXT optical upper limit
  12. GRB 261017A: Enhanced Swift-XRT position
  13. GRB 261017A: Fermi GBM Observation
  14. GRB 261017A: Swift detection of a burst
  15. GRB 261011A: 1.3m DFOT optical upper limit
  16. GRB 261010A: Pan-STARRS z-band imaging and upper limit
  17. GRB 261010A: LBT tentative near-infrared detection
  18. GRB 261010A: Glowbug gamma-ray detection
  19. GRB 261011A: Later-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  20. GRID detection of GRB 261010A
  21. GRB 261011A: GECAM-B observation
  22. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  23. GRB 261010A: Swift-XRT refined Analysis
  24. GRB 261011A: Swift-XRT refined Analysis
  25. GRB 261011A: Enhanced Swift-XRT position
  26. GRB 261011A: 10.4m GTC spectroscopic redshift (z = 2.407)
  27. GRB 261011A: Swift-BAT refined analysis
  28. GRB 261010A: 10.4m GTC spectroscopy of the galaxy 2" from the afterglow
  29. GRB 261011A: REM optical/NIR observations
  30. Konus-Wind detection of GRB 261010A
  31. Konus-Wind detection of GRB 261011A
  32. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  33. GRB 261010A: Swift-BAT refined analysis
  34. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  35. GRB 261011A: Optical followup from Sichuan South Observatory
  36. GRB 261011A: GMG Optical Observation
  37. GRB 261011A: Liverpool Telescope optical observations
  38. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  39. GRB 261010A: NOT confirmation of the optical afterglow
  40. GRB 261010A: Fermi GBM Observation
  41. GRB 261011A: continued LCO optical observations
  42. GRB 261011A: GROWTH-India Telescope optical observations
  43. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  44. Swift GRB 261011A: Global MASTER-Net observations report
  45. GRB 261011A: Optical follow-up observations with Kinder
  46. GRB 261011A: SVOM/VT optical observation from VHF data
  47. GRB 261011A: LCO optical observations
  48. GRB 261011A: TRT optical afterglow detection
  49. GRB 261011A: GOTO optical counterpart detection
  50. GRB 261011A: Swift detection of an unusual burst
  51. GRB 261010A: Enhanced Swift-XRT position
  52. GRB 261010A: possible optical afterglow detected with the 1.5m OSN
  53. GRB 261010A: NOT possible optical counterpart
  54. GRB 261010A: Swift detection of a burst
  55. EP261006a: Swift/XRT detection of the fading X-ray counterpart
  56. GRB 261007A: Swift-XRT afterglow detection
  57. GRB 261007A: Swift ToO observations
  58. GRB 261005B: Swift-BAT refined analysis
  59. GRB 261005B: Swift-XRT refined Analysis
  60. GRB 261005B: Swift/UVOT Upper Limits
  61. GRB 261005B: J-band upper limit with WINTER
  62. GRB 261005B: Fermi GBM Observation
  63. GRB 261005B: Enhanced Swift-XRT position
  64. GRB 261005B: Swift detection of a burst
  65. EP#01709320865: Swift-XRT observations
  66. Trigger_21915: Swift ToO observations (retracted)
  67. GRB 260924A: Swift/UVOT UV grism spectrum results
  68. GRB 260925A: Swift-BAT refined analysis
  69. Swift Trigger 1513439: consistent with noise and not astrophysical
  70. GRB 260924A: COLIBRÍ optical observations
  71. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  72. GRB 260925A: Swift-XRT refined Analysis
  73. Swift Trigger 1513439 is probably not a GRB
  74. GRB 260925A: Swift/UVOT Upper Limits
  75. Konus-Wind detection of GRB 260924A
  76. GRB 260922A: Glowbug gamma-ray detection
  77. GRB 260925A: Enhanced Swift-XRT position
  78. GRB 260925A: COLIBRÍ optical upper limits
  79. GRB 260925A: FRAM-Auger optical limit
  80. GRB 260924A: Ondrejov D50 optical afterglow detection
  81. GRB 260924A: SVOM/GRM observation
  82. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  83. GRB 260925A: Swift detection of a burst
  84. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  85. GRB 260924A: Swift/UVOT Detection
  86. GRB 260924A: Swift-BAT refined analysis
  87. GRB 260924A: NuSTAR detection of prompt emission
  88. GRB 260924A: Swift/UVOT Upper Limits
  89. GRB 260924A: Swift-XRT refined Analysis
  90. Konus-Wind detection of GRB 260922A
  91. GRB 260922A: NuSTAR detection of prompt emission
  92. GRB 260921A: NuSTAR detection of prompt emission
  93. GRB 260921A: SVOM/GRM observation
  94. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  95. GRB 260924A: Fermi GRB Observation
  96. Konus-Wind detection of GRB 260921A (possible merger-origin)
  97. GRB 260924A: Fermi-LAT detection of a bright burst
  98. GRB 260924A: AstroSat CZTI detection
  99. GRB 260924A: NOT optical counterpart confirmation
  100. GRB 260924A: detection of a bright optical afterglow by the 1.5m OSN telescope

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