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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"

32751 results found.

  1. GRB 220408A: RATIR Optical and NIR Observations
  2. GRB 220403B: 1.3m DFOT Optical upper limit
  3. GRB 220408A: 1.3m DFOT Optical upper limit
  4. GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
  5. GRB 220403C: Swift-XRT observations
  6. GRB 220408A: redshift lower limit estimating
  7. GRB 220408A: NOT optical observations and archival detection
  8. GRB 220408B: AstroSat CZTI detection
  9. GRB 220408A: LCO Optical Afterglow Detection
  10. GRB 220408A: Swift-XRT refined Analysis
  11. GRB 220403C: Swift ToO observations
  12. Fermi GRB 220408B: Global MASTER-Net observations report
  13. GRB 220408A: GIT optical upper limit
  14. GRB 220408A: Fermi GBM observation
  15. GRB 220408A: Swift/UVOT Detection
  16. GRB 220408A: Xinglong-2.16m optical upper limit
  17. Chandra upper limit at the location of GRB 220408A
  18. GRB 220408A: KAIT Optical Observations
  19. Fermi GRB 220408A: Global MASTER-Net observations report
  20. ZTF22aaajecp/AT2022cmc: continued optical observations (Mondy, SAO RAS, CrAO)
  21. Fermi-LAT Gamma-ray Observations of IceCube-220405B
  22. GRB 220403B: Mondy optical upper limit
  23. IceCube-220405A: No Candidate Counterparts from the Zwicky Transient Facility
  24. IceCube-220405B: No Candidate Counterparts from the Zwicky Transient Facility
  25. GRB 220404A: Swift-BAT refined analysis
  26. GRB 220403B: Kitab optical observations
  27. Fermi-LAT Gamma-ray Observations of IceCube-220405A
  28. GRB 220403B: Swift-BAT refined analysis
  29. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  30. GRB 220403B: Fermi GBM detection
  31. GRB 220403B: Swift-XRT refined Analysis
  32. GRB 220403B: LBT observations
  33. Swift GRB 220403B: Global MASTER-Net observations report
  34. GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
  35. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  36. GRB 220403A: Tautenburg observations
  37. Fermi GRB 220403A: Global MASTER-Net observations report
  38. GRB 220401A: Swift/BAT-GUANO detection outside the coded FOV
  39. GRB 220401A: Fermi GBM observation
  40. Fermi GRB 220401B: Global MASTER-Net observations report
  41. Fermi Gamma-ray Burst Monitor trigger 220331776/670444627 is not a GRB
  42. Fermi GRB 220330A: Global MASTER-Net observations report
  43. ZTF22aaajecp/AT2022cmc: 1.3m DFOT Optical observations
  44. GRB 220325A: GRANDMA observations
  45. GRB 220320A: Detection by VZLUSAT-2
  46. Konus-Wind observation of GRB 220320A
  47. GRB 220325A: Swift/UVOT Upper Limits
  48. GRB 211024B: Host galaxy redshift from X-shooter/VLT
  49. GRB 220325A: Swift-BAT refined analysis
  50. ZTF22aaajecp/AT2022cmc: continued optical observations (Mondy, TSHAO, AbAO)
  51. GRB 220325A: Tautenburg observations
  52. GRB 220325A: LCO Optical Upper Limits
  53. GRB 220325A: Swift-XRT refined Analysis
  54. GRB 220325A: 1.3m DFOT Optical upper limit
  55. Fermi GBM Sub-Threshold Detection of GRB 220325A
  56. GRB 220325A: MASTER Global Robotic Net optical observations
  57. GRB 220323A: AstroSat CZTI detection
  58. GRB 220319A: GRANDMA observations
  59. GRB 220323A: AGILE/MCAL detection
  60. IPN triangulation of GRB 220320A
  61. GRB 220319A: Swift-BAT refined analysis
  62. GRB 220316A: AstroSat CZTI detection
  63. GRB 220320A: AstroSat CZTI detection
  64. GRB 220317A: Fermi GBM detection
  65. GRB 220319A: MITSuME Akeno optical upper limits
  66. GRB220319A: Optical observations from NOT
  67. GRB 220319A: LCO Optical Upper Limit
  68. GRB 220319A: Mondy optical uper limit
  69. GRB 220319A: Swift-XRT refined Analysis
  70. GRB 220319A: MASTER Global Robotic Net optical observations
  71. Fermi-LAT Gamma-ray Observations of IceCube-220317A
  72. GRB 220317A: Swift/BAT-GUANO detection outside the coded FOV
  73. GRB 220310A: MITSuME Akeno optical observation
  74. IceCube-220317A: MASTER Global Robotic Net optical observations
  75. GRB 220315A: MASTER Global Robotic Net optical observations
  76. GRB 220311A: Fermi GBM observation
  77. GRB 220306B: Swift/UVOT Upper Limits
  78. GRB 220311A: MITSuME Akeno optical upper limits
  79. IPN triangulation of GRB 220310A
  80. GRB 220310C: Fermi GBM observation
  81. GRB 210722A: TAROT Reunion observatory optical light curve
  82. GRB 210222B: TAROT Reunion observatory optical light curve
  83. GRB 201021C: TAROT Reunion observatory optical light curve
  84. GRB 220310A: K-800 of Terskol observatory optical upper limit
  85. GRB 220310A: [KAO-Egypt] SDSS r, i observation
  86. Konus-Wind detection of GRB 220310A
  87. GRB 220310C: Swift ToO observations
  88. GRB 220310C: Swift/BAT-GUANO candidate arcminute localization
  89. GRB 220311A: MASTER OT retraction
  90. ZTF22aabjpxh/AT2022cva (GRB 220219B): evidence of supernova in LBT spectra
  91. GRB 220310A: GIT confirmation of optical afterglow.
  92. GRB 220306B: Nanshan/NEXT optical upper limit
  93. ZTF22aabjpxh/AT2022cva (GRB 220219B): continued optical observations, possible photometric evidence of SN
  94. Fermi GBM Detection of GRB 220308A
  95. GRB 220308A: AGILE detection
  96. GRB 220310A: MASTER optical counterpart detection
  97. GRB 220310A: Swift ToO observations
  98. GRB 220310A: CALET Gamma-Ray Burst Monitor detection
  99. ZTF22aaajecp/AT2022cmc: Hubble Space Telescope Observations
  100. Fermi GRB 220310B: Global MASTER-Net observations report

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