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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').
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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"

19689 results found.

  1. Fermi GRB 210529B: Global MASTER-Net observations report
  2. GRB 210528B: DDOTI Upper Limits on the Afterglow
  3. GRB 210528B: MITSuME Akeno optical upper limits
  4. GRB 210527A: Swift/UVOT Observations
  5. GRB 210527A: GIT optical upper limit
  6. GRB 210527A: MITSuME Akeno optical upper limits
  7. GRB 210527A: RATIR Optical and NIR Observations
  8. GRB 210527A: Enhanced Swift-XRT position
  9. GRB 210527A: Swift-XRT observations
  10. GRB 210306A: LBT observations of the likely host galaxy
  11. ZTF21aayokph (AT2021lfa): LBT optical observations
  12. Fermi GRB 210524B: DDOTI Upper Limits on the Afterglow
  13. IPN triangulation of GRB 210524A
  14. GRB 210522A: GECAM detection
  15. ZTF21aayokph (AT2021lfa): continued Assy optical observations
  16. GRB 210520A: Tiled Swift observations
  17. GRB 210517A: KCT optical upper limit
  18. Fermi trigger No 643065622: Global MASTER-Net observations report
  19. GRB 210518.889: DDOTI Upper Limits on the Afterglow
  20. Fermi-LAT Gamma-ray Observations of IceCube-210516A
  21. IceCube-210516A: No significant detection in HAWC
  22. GRB 210517A: Swift/UVOT Upper Limits
  23. GRB 210515C: Swift/UVOT Upper Limits
  24. GRB 210517A: VLT/X-shooter optical afterglow and redshift
  25. GRB 210517A: Enhanced Swift-XRT position
  26. GRB 210517A: Swift detection of a burst
  27. GRB 210514A: Swift/UVOT Upper Limits
  28. AMON IC_HAWC NuEm-210515A / NuEm-210515B : No neutrino counterpart detected with ANTARES
  29. GRB 210515C: Swift-XRT refined Analysis
  30. GRB 210514A: Swift-XRT refined Analysis
  31. GRB 210514A: Enhanced Swift-XRT position
  32. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  33. Short GRB 210323A: likely host galaxy detection
  34. GRB 210511B: DDOTI Upper Limits on the Afterglow
  35. IPN triangulation of GRB 210427A
  36. GRB 210511B: Fermi GBM observation
  37. Fermi GRB 210510A: DDOTI Upper Limits on the Afterglow
  38. IceCube-210510A: DDOTI Upper Limits
  39. GRB 210509A: RATIR Optical and NIR Upper Limits
  40. GRB 210509A: Swift/UVOT Upper Limits
  41. GRB 210509A: Swift-BAT refined analysis
  42. GRB 210509A: Enhanced Swift-XRT position
  43. GRB 210509A: Swift-XRT observations
  44. HAWC-210507A: No neutrino counterpart candidates in ANTARES search
  45. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  46. GRB 210506A: Swift-XRT observations
  47. Alert from the HAWC Burst Monitor HAWC-210507A
  48. HAWC GRB 210507.443: DDOTI Upper Limit
  49. GRB 210506A: Nanshan/NEXT optical upper limit
  50. GRB 210506A: TNG NIR upper limits
  51. ZTF21aayokph (AT2021lfa): Mondy and Koshka observatory optical observations
  52. Lowell Discovery Telescope Observations of ZTF21aayokph (AT2021lfa)
  53. ZTF21aayokph (AT2021lfa): Assy optical observations
  54. GRB 210506A: Swift ToO observations
  55. ZTF21aayokph (AT2021lfa): Nanshan/NEXT optical upper limit
  56. GRB 210504A: Lowell Discovery Telescope optical observations
  57. GRB 210504A: VLT X-shooter redshift
  58. GRB 210504A: Swift-XRT refined Analysis
  59. DDOTI Observations of ZTF21aayokph (AT2021lfa)
  60. GRB 210504A: MITSuME Akeno optical upper limits
  61. Fermi GRB 210503A: DDOTI Upper Limits on the Afterglow
  62. GRB 210504A: Swift/UVOT Detection
  63. GRB 210504A: Swift detection of a burst
  64. Swift Detection of MAXI J1803-298 including an optical counterpart
  65. GRB 210424B: MITSuME Akeno optical upper limits
  66. GRB 210430A: Swift detection of a burst
  67. Delayed GRB GCN Notices from Swift
  68. Fermi GRB 210427A: Global MASTER-Net observations report
  69. GRB 210420B: Assy optical observations
  70. GRB 210424.694: DDOTI Upper Limits on the Afterglow
  71. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  72. GRB 210420B: Zeiss-1000 of Koshka optical observations
  73. GRB 210421B: Swift-XRT observations
  74. GRB 210420B: continued Tautenburg observations
  75. GRB 210421A: GECAM detection
  76. GRB 210421A: Swift/UVOT Upper Limits
  77. GRB 210420B: follow-up photometry of the optical afterglow at Konkoly
  78. GRB 210421A: MITSuME Akeno optical upper limits
  79. GRB 210421B: Swift ToO observations
  80. GRB 210419C: Swift/UVOT Upper Limits
  81. GRB 210421A: Enhanced Swift-XRT position
  82. GRB 210420B: RATIR Optical and NIR Observations
  83. GRB 210420B: Tautenburg observations
  84. GRB 210420B: Swift/UVOT Detection
  85. GRB 210413B: MITSuME Okayama optical upper limits
  86. GRB 210419C: MITSuME Akeno optical upper limits
  87. GRB 210420B: DDOTI Detection of the Afterglow
  88. GRB 210421A: DDOTI Upper Limit
  89. GRB 210420B: Multiband photometry from NOT
  90. GRB 210420B: Montarrenti Observatory optical afterglow detection
  91. GRB 210421A: Swift detection of a burst
  92. GRB 210420B: Optical observations
  93. GRB 210420B: MASTER optical counterpart detection
  94. GRB 210419C: RATIR Optical and NIR Upper Limits
  95. GRB 210419C: Montarrenti Observatory Upper Limit
  96. GRB 210419A: Swift/UVOT Upper Limits
  97. GRB 210419C: Enhanced Swift-XRT position
  98. GRB 210419C: Swift detection of a burst
  99. GRB 210419A: Enhanced Swift-XRT position
  100. GRB 210419A: Swift detection of a burst

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