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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"

16320 results found.

  1. LIGO/Virgo S190408an: MASTER OT is 27 day old ATLAS SN candidate and unrelated
  2. LIGO/Virgo S190408an: MASTER OT detection
  3. LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
  4. LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
  5. Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
  6. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  7. GRB 190404C: Swift-XRT observations
  8. GRB190404C: GROWTH-India discovery of optical counterpart
  9. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  10. GRB 190331B: BOOTES-3/YA optical observations
  11. IceCube-190331A: MASTER optical follow-up observations
  12. GRB 190326A: 2.2m CAHA telescope optical limit
  13. GRB 190326A: MITSuME Okayama optical upper limits
  14. GRB190324A: MASTER OT observations
  15. GRB 190324A: VLT/X-shooter redshift
  16. GRB 190320A: Swift/UVOT Upper Limits
  17. GRB190320A: MASTER GRB counterpart decay
  18. GRB190311A: MITSuME Akeno optical observation
  19. Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
  20. GRB 190311A: OSN optical afterglow detection
  21. GRB 190311A: Mondy optical observations
  22. GRB 190311A: Liverpool Telescope observations
  23. GRB 190311A: NOT optical counterpart
  24. GRB190305A: MASTER Global Robotic Net optical observation
  25. GRB 190311A: Mondy optical observations
  26. GRB 190311A: GMG observation
  27. GRB 190311A: TSHAO optical observations
  28. GRB190311A: MASTER Global Robotic Net OT optical observation
  29. GRB 190311A: NEXT-0.6m optical afterglow detection
  30. GRB 190311A: Mondy optical observations
  31. GRB 190311A: Swift detection of a burst with optical counterpart
  32. IceCube-190221A: MASTER Global Robotic Net optical observation
  33. GRB 190219A: CrAO and AbAO optical upper limit
  34. GRB 190220B: Kitab Observatory optical upper limit
  35. GRB 190220B: BOOTES-4 optical observation
  36. GRB 190219A: NOT optical afterglow candidate
  37. GRB 190219A: NEXT-0.6m optical upper limit
  38. GRB 190220A: Swift detection of a burst with an optical counterpart
  39. GRB190219A: MASTER Global Robotic Net optical observation
  40. GRB 190219A: BOOTES-1 optical limits
  41. GRB190211A: GROWTH-India detection of optical afterglow
  42. GRB 190211A: Swift/UVOT Detection
  43. GRB 190211A: DOAO optical observation
  44. GRB190211A: MITSuME Akeno optical observation
  45. GRB 190211A: NOT optical observations
  46. GRB 180703A: VLT/MUSE host galaxy redshift measurement
  47. GRB 190211A: BOOTES-4/MET optical afterglow confirmation
  48. GRB190211A: MASTER Global Robotic Net optical observation
  49. GRB 190211A: NEXT-0.6m optical afterglow detection
  50. GRB 190202A: Terskol 2-m optical observations
  51. GRB 190203A: Mondy optical observations
  52. GRB190202A: GROWTH-India detection of optical afterglow
  53. GRB 190202A: Xinglong-2.16m optical observations
  54. GRB 190202A: SAO RAS further optical observations
  55. GRB 190204A: SAO RAS optical observations
  56. GRB 190204A: Mondy optical upper limit
  57. GRB 190203A: COATLI Optical Observations
  58. GRB 190204A: COATLI Optical Detection of the Fading Afterglow
  59. GRB 190204A: Swift detection of a burst with a possible optical counterpart
  60. Swift Trigger 887541: MASTER optical observation
  61. GRB 190203A: MASTER OT detection
  62. GRB 190203A: SAO RAS optical observations, afterglow fading
  63. GRB 190203A: Koshka Zeiss-1000 optical upper limit
  64. GRB 190203A: Swift detection of a burst with an optical counterpart
  65. GRB 190202A: SAO RAS optical observations
  66. GRB 190202A: TSHAO optical observations
  67. GRB 190202A: NOT optical observations
  68. GRB 190202A: McDonald 0.8-m telescope optical observation
  69. GRB 190202A: LCO-CTIO optical observations
  70. GRB 190202A: GOTO optical observations
  71. GRB 190202A: Koshka Zeiss-1000 optical observations
  72. GRB 190202A: Swift detection of a burst with an optical counterpart
  73. GRB 190129B: GOTO optical observations
  74. GRB 190129B: Swift/UVOT Upper Limits
  75. GRB 190129B: ePESSTO NTT optical observations
  76. GRB 190129B: MASTER Global Robotic Net optical observation
  77. Swift Trigger 886157: MASTER optical observation
  78. GRB 190114C: Optical follow-up from HCT
  79. Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
  80. GRB 190123A: IKI-GRB-FuN optical upper limit
  81. GRB 190123A: NEXT-0.6m optical limit
  82. GRB 190114C: CHILESCOPE optical observations
  83. GRB 190123A: AROMA-N Optical Observation
  84. GRB 190123A: Swift/UVOT Upper Limits
  85. GRB 190123A: COATLI Optical Observations
  86. GRB190123A: MITSuME Akeno optical upper limits
  87. GRB 190123A: GMG observational limit
  88. GRB 190123A: GOTO optical limit
  89. GRB 190123A: BOOTES-4/MET optical limit
  90. GRB 190123A: MASTER Global Robotic Net optical observation
  91. GRB 190114C: RTT150 optical observations
  92. GRB 190114C: UKIRT JHK observation continuation - steady fading?
  93. GRB 190114C: REM optical/NIR detection (CORRECTION)
  94. GRB 190114C: RATIR Optical and NIR Detections
  95. GRB 190114C: RT-22 detection at 36.8 GHz
  96. GRB 190114C: COATLI Optical Detection
  97. GRB 190114C: ePESSTO NTT optical observations
  98. GRB 190114C: Continued UKIRT JHK observation
  99. GRB 190114C: continued CHILESCOPE optical obs
  100. GRB190114C: ATCA detection of the radio afterglow

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