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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.

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

16272 results found.

  1. GRB 210104A: Assy optical observations
  2. GRB 210104A: MITSuME Akeno optical observation
  3. GRB 210104A: BOOTES-4/MET early optical afterglow detection
  4. GRB 210104A: GWAC-F60A optical afterglow observations
  5. GRB 210104A: Swift detection of a burst with a bright optical counterpart
  6. INTEGRAL Weak #8913: AROMA-N Optical Observation
  7. GRB 201229A: Swift/UVOT Detection
  8. GRB 201216C: TSHAO, Terskol, Mondy optical upper limits
  9. GRB 201227A: Chilescope optical observations, possible optical counterpart
  10. GRB 201227A: GRAWITA VST-ESO PARANAL observations
  11. GRB 201229A: AbAO optical afterglow detection, TSHAO optical upper limit
  12. GRB 201229A: SAO RAS optical observations
  13. GRB 201229A: Nanshan/NEXT optical upper limit
  14. GRB 201223A: SVOM-GWAC detected the optical counterpart during prompt emission phase
  15. GRB 201104B: Maidanak and CrAO optical observations
  16. GRB 201229A: Swift detection of a burst with a possible optical counterpart
  17. GRB 201020B: Assy, Koshka, Mondy and Maidanak optical observations
  18. ZTF20acozryr/AT2020yxz (GRB 201103B): Maidanak optical observations
  19. GRB 201223A: AROMA-N Optical Observation
  20. GRB 201223A: HCT optical upper limit
  21. GRB 201223A: AbAO optical observations
  22. GRB 201223A: 1.3m DFOT and 1.04m ST optical observations
  23. GRB 201223A: NOT optical upper limit and NEXT powerlaw decay
  24. GRB 201223A: GROWTH-India Telescope (GIT) photometric follow-up.
  25. GRB 201223A: Mondy and Kitab optical observations
  26. GRB 201223A: GWAC-F60A optical afterglow observations
  27. GRB 201223A: iTelescope optical afterglow observations
  28. GRB 201223A: MITSuME Akeno optical observation
  29. GRB 201223A: BOOTES-4/MET early optical observation
  30. GRB 201223A: Nanshan/NEXT early optical afterglow detection
  31. GRB 201223A: Swift detection of a burst with a bright optical counterpart
  32. Swift GRB201223.75: Global MASTER-Net OT detection
  33. GRB 201221D: 3.6m DOT optical observations
  34. GRB 201221D: SMA submm observation
  35. GRB 201221D: MMT MMIRS detection of marginally extended source
  36. GRB 201221D: LCOGT upper limits
  37. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy
  38. Short GRB201221D: High Redshift from OSIRIS/GTC
  39. GRB 201221D: Swift/UVOT Upper Limits
  40. GRB 201221D: Lowell Discovery Telescope afterglow observations
  41. GRB 201221D: FRAM-ORM optical limit
  42. GRB 201221D: Nanshan/NEXT early optical upper limit
  43. GRB 201221D: candidate optical counterpart from the NOT
  44. GRB 201221A: Swift/UVOT Upper Limits
  45. GRB 201221C: MASTER optical observtion
  46. GRB 201221A: FRAM-Auger optical limit
  47. GRB 201209A: Mondy optical observations, afterglow confirmation
  48. GRB 201214A: TSHAO optical upper limit
  49. GRB 201214A: 1.3m DFOT, optical upper limits
  50. GRB 201216C: Liverpool Telescope First Hour Observations
  51. GRB 201216C: VLT X-shooter spectroscopy and potential high redshift of a VHE-emitting GRB
  52. GRB 201216C: Swift/UVOT Upper Limits
  53. GRB 201214B: MITSuME Akeno optical upper limits
  54. GRB 201214B: Lowell Discovery Telescope optical observations
  55. GRB 201214A: Mates' birthday GRB optical limit from FRAM-ORM
  56. GRB 201015A: optical observations and supernova identification
  57. GRB 201203A: Zeiss-1000 (Koshka observatory) optical upper limit
  58. GRB 201203A: 1.3m DFOT, optical upper limits
  59. GRB 201209A: Swift/UVOT Upper Limits
  60. GRB 201208A: LCO observations
  61. GRB 201209A: Xinglong-2.16m likely optical afterglow detection
  62. IceCube-201130A: Optical and NIR Imaging Follow-up by Kanata Telescope
  63. GRB 201209A: KAIT Optical Upper Limit
  64. GRB 201209A: FRAM-Auger optical limit
  65. GRB 201203A: GROWTH-India Telescope optical upper limit.
  66. GRB 201203A: MITSuME Okayama optical upper limits
  67. GRB 201203A: KAIT Optical Upper Limit
  68. GRB 201203A: FRAM-Auger optical limit
  69. Swift-XRT observations of IceCube 201130A
  70. GRB 201128A: Swift/UVOT Upper Limits
  71. Fermi trigger No 628140709: DDOTI/OAN optical observations report
  72. IceCube-201114A: Updated photometry for three DECam candidate optical counterparts
  73. IceCube-201114A: DECam observations and candidate optical counterpart
  74. INTEGRAL Weak #8831 and #8832: AROMA-N Optical Observation
  75. ZTF20acozryr/AT2020yxz (GRB 201103B): SAO RAS optical observations
  76. ZTF20acozryr/AT2020yxz (GRB 201103B): correction to the GCN #28883 CrAO/ZTSh optical observations
  77. IceCube 201114A: Swift followup of Fermi J0703.5+0505
  78. INTEGRAL Weak#8825: AROMA-N Optical Observation
  79. GRB 201116A: NOT optical observations
  80. GRB 201116A: Swift-XRT afterglow detection
  81. INTEGRAL Weak#8811: AROMA-N Optical Observation
  82. VLASS identifies possible radio counterparts to IceCube-201115A, including a bright BL Lac candidate
  83. ZTF20acozryr/AT2020yxz (GRB 201103B): CrAO/ZTSh optical observations
  84. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy continued optical observations
  85. ZTF20acozryr/AT2020yxz (GRB 201103B): Flattening of the optical light curve
  86. ZTF20acozryr (GRB 201103B): GROWTH-India Telescope optical observations
  87. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy, Kitab, TSHAO optical observations
  88. GRB 201104B: continued TSHAO optical observation
  89. GRB 201104B: MITSuME Akeno optical observation
  90. GRB 201103B: GMG observation (2nd epoch)
  91. ZTF20acozryr/AT2020yxz (GRB 201103B): Assy optical observations
  92. GRB201103B: GMG observation
  93. GRB 201104B: 1.3m DFOT optical observations
  94. GRB 201104A: Swift-XRT observations
  95. GRB 201104B: Kitab optical observations
  96. GRB 201103B (ZTF20acozryr/AT2020yxz): Xinglong-2.16m optical observations
  97. GRB 201104B: TSHAO optical observation
  98. GRB 201103B (ZTF20acozryr/AT2020yxz): VLT/X-shooter redshift
  99. GRB 201103B (ZTF20acozryr/AT2020yxz): Nanshan/NEXT-0.6m optical observations
  100. IPN triangulation of GRB 201103B (consistent with ZTF20acozryr/AT2020yxz)

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