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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"

21094 results found.

  1. Fermi trigger No 720224759: Global MASTER-Net observations report
  2. Swift GRB 231028A: Global MASTER-Net observations report
  3. IceCube Alert 231027.18: Global MASTER-Net observations report
  4. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  5. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  6. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  7. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  8. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  9. GRB 231024A: GOTO optical counterpart candidate
  10. Fermi trigger No 719846439: Global MASTER-Net observations report
  11. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  12. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  13. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  14. Fermi GRB 231020A: Global MASTER-Net observations report
  15. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  16. GRB 231017A: 1.3m DFOT Optical upper limit
  17. IceCube-231004A: Upper limits from Fermi-GBM Observations
  18. Fermi GRB 231019A: Global MASTER-Net observations report
  19. GRB 231017A: Swift/UVOT Upper Limit
  20. GRB 230911C: ATCA detection of possible radio counterpart
  21. GRB 231017A: GOTO optical upper limits
  22. IC231004A: Classification of AT2023uqf/ZTF23abidzvf as a rapidly-evolving supernova with CSM interaction
  23. GRB 231017A: Swift-XRT observations
  24. GRB 231017A: Swift ToO observations
  25. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  26. Fermi-LAT gamma-ray observations of IceCube-231014A
  27. (correction) Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field
  28. Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field.
  29. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  30. Fermi-LAT gamma-ray observations of IceCube-231004A
  31. transient AT2023sva: radio observations with AMI-LA
  32. AT2023sva / GRB230916B: GIT observations of the afterglow
  33. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  34. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  35. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  36. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  37. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  38. LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP
  39. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  40. transient AT2023sva: imaging and spectroscopic observations from MISTRAL at Observatoire de Haute-Provence
  41. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  42. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  43. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  44. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  45. AT 2023sva: NOT observations of the ZTF candidate afterglow
  46. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  47. GRB 230812B: Radio observations with the uGMRT
  48. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  49. Swift GRB230916.18: Global MASTER-Net observations report
  50. Fermi trigger No 716572242: Global MASTER-Net observations report
  51. Fermi trigger No 716544961: Global MASTER-Net observations report
  52. Fermi-LAT gamma-ray observations of IceCube-230914A
  53. Swift GRB230916.19: Global MASTER-Net observations report
  54. Swift GRB230916.18: Global MASTER-Net observations report
  55. Swift GRB230916.13: Global MASTER-Net observations report
  56. Swift GRB230916.12: Global MASTER-Net observations report
  57. Swift GRB230916.11: Global MASTER-Net observations report
  58. GRB 230906A: optical counterpart
  59. GRB 230911A: Swift-XRT afterglow detection
  60. Fermi trigger No 716449174: Global MASTER-Net observations report
  61. IceCube Alert 230914.22: Global MASTER-Net observations report
  62. Fermi trigger No 716419312: Global MASTER-Net observations report
  63. Swift GRB230913.70: Global MASTER-Net observations report
  64. Swift GRB230913.70: Global MASTER-Net observations report
  65. GRB 230911A: Swift ToO observations
  66. Fermi GRB 230913A: Global MASTER-Net observations report
  67. GRB 230911A: GOTO optical counterpart candidate
  68. GRB 230906A: Chandra detection of the X-ray afterglow
  69. Swift GRB 230911C: Global MASTER-Net observations report
  70. GRB 230911C: Swift/UVOT Upper Limits
  71. Fermi trigger No 716145795: Global MASTER-Net observations report
  72. GRB 230911C: GOTO optical upper limits
  73. Fermi GRB 230911B: Global MASTER-Net observations report
  74. GRB 230903A: TESS observations of optical emission
  75. GRB 230906A: Swift/UVOT Upper Limits
  76. GRB 230818A: radio observation with the VLA
  77. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  78. GRB 230906A: Swift-XRT observations
  79. GRB 230906A: Swift ToO observations
  80. Fermi GRB 230906A: Global MASTER-Net observations report
  81. GRB 230903A: VLT/X-shooter optical observations
  82. Fermi trigger No 715552087: Global MASTER-Net observations report
  83. Fermi trigger No 715429986: Global MASTER-Net observations report
  84. Fermi GRB 230903A: Global MASTER-Net observations report
  85. Fermi GRB 230904A: Global MASTER-Net observations report
  86. Swift GRB230903.72: Global MASTER-Net observations report
  87. Integral GRB230902.00: Global MASTER-Net observations report
  88. GRB 230827B: Swift-XRT afterglow detection
  89. GRB 230827B: Swift ToO observations
  90. Subject: GRB230826A: Swift/UVOT upper limits
  91. Fermi trigger No 714809315: Global MASTER-Net observations report
  92. GRB 230827.256: AKO Optical follow-up of ZTF23abaanxz (AT 2023qxj)
  93. Fermi GRB 230827A: Global MASTER-Net observations report
  94. Swift J1727.8-1613 (GRB 230824A): Osservatorio Astronomico "Nastro Verde" optical observations
  95. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  96. Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations
  97. Swift J1727.8-1613 (GRB 230824A): Leavitt Observatory optical observations
  98. GRB 230826A: Mondy optical observations
  99. Swift J1727.8-1613 (GRB 230824A): GAD Observatory La Spezia - optical observations
  100. Swift GRB230826.81: Global MASTER-Net observations report

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