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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"

21999 results found.

  1. IceCube-230708A: Upper limits from Swift/BAT-GUANO
  2. Fermi trigger No 710741042: Global MASTER-Net observations report
  3. IceCube-230707A: No candidates detected by Swift-XRT
  4. IceCube-230707A: No candidates from the Zwicky Transient Facility
  5. Fermi-LAT gamma-ray observations of IceCube-230708A
  6. Fermi-LAT gamma-ray observations of IceCube-230707B
  7. Fermi-LAT gamma-ray observations of IceCube-230707A
  8. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  9. GRB 230707A: Swift-XRT observations
  10. IceCube Alert 230708.35: Global MASTER-Net observations report
  11. IceCube Alert 230707.71: Global MASTER-Net observations report
  12. GRB 230707A: Swift ToO observations
  13. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  14. ZTF23aaoohpy/AT2023lcr : HCT follow-up observations
  15. Fermi GRB 230707A: Global MASTER-Net observations report
  16. Integral GRB230706.70: Global MASTER-Net observations report
  17. LIGO/Virgo/KAGRA S230627c: GECKO optical follow-up observations of host galaxy candidates and ZTF23aaptsuy/AT2023lxu
  18. ZTF23aaoohpy/AT2023lcr: AMI-LA radio detection
  19. Fermi trigger No 710117592: Global MASTER-Net observations report
  20. GRB 230328B: LBT detection of the likely host galaxy
  21. LIGO/Virgo/KAGRA S230627c: observations of ZTF23aaptsuy/AT2023lx in AbAO observatory
  22. GRB 230628E: Swift/UVOT Detection
  23. GRB 230628E: ATCA rapid radio follow-up
  24. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  25. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  26. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): ALMA 100 GHz Detection
  27. GRB 230628E - VLT spectroscopic observations
  28. ZTF23aaoohpy/AT2023lcr: LBT observations
  29. Fermi GRB 230628C: Global MASTER-Net observations report
  30. GRB230628E: VLT optical identification of afterglow candidate
  31. Fermi GRB 230628D: Global MASTER-Net observations report
  32. Swift GRB230628.93: Global MASTER-Net observations report
  33. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  34. LIGO/Virgo/KAGRA S230516az: GOTO candidate counterpart GOTO23hu ruled out by Zwicky Transient Facility observations
  35. LIGO/Virgo/KAGRA S230627c: Additional observations from the Zwicky Transient Facility
  36. AT2023lcr: JCMT SCUBA-2 sub-mm observations
  37. LIGO/Virgo/KAGRA S230627c: ATLAS information on the ZTF candidates
  38. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  39. LIGO/Virgo/KAGRA S230627c: Global MASTER-Net observations report
  40. LIGO/Virgo/Kagra S230627c: NED Galaxies in the Localization Volume
  41. LIGO/Virgo/KAGRA S230627c: Zwicky Transient Facility observations and candidates
  42. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  43. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  44. GRB 230623A: Swift-XRT observations
  45. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  46. ZTF23aaoohpy/AT2023lcr: further SAO RAS observations
  47. ATLAS23msn/ZTF23aaoohpy/AT2023lcr: Zeiss-1000 of Koshka observatory optical observations
  48. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  49. GRB 230623A: Tiled Swift observations
  50. MAXI GRB 230623A: MASTER optical observations
  51. GRB 230623A: Tiled Swift observations
  52. GRB 230622A: ATCA rapid radio follow-up
  53. Swift GRB 230622A: Global MASTER-Net observations report
  54. LIGO/Virgo/KAGRA S230615az: LBT spectroscopic classification of GOTO23hn
  55. LIGO/Virgo S230622e: Global MASTER-Net observations report
  56. LIGO/Virgo S230621bq: Global MASTER-Net observations report
  57. LIGO/Virgo S230621ad: Global MASTER-Net observations report
  58. LIGO/Virgo/KAGRA S230615az: LBT spectroscopic redshift of the host galaxy of GOTO23hn
  59. ZTF23aaoohpy/AT2023lcr: SAO RAS observations
  60. Fermi trigger No 709083929: Global MASTER-Net observations report
  61. Fermi GBM-230619: A soft subthreshold candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  62. AT2023lcr: VLA radio detection
  63. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  64. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  65. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  66. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Swift/UVOT detection
  67. LIGO/Virgo S230620au: Global MASTER-Net observations report
  68. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  69. AT2023lcr: Neil Gehrels Swift Observatory X-ray detection
  70. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): Kinder observations with Lulin observatory and a probable plateau in the g-band light curve
  71. AT2023lcr: Pan-STARRS & ATLAS Observations
  72. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  73. ZTF23aaoohpy/AT2023lcr: Xinglong-2.16m optical observations
  74. LIGO/Virgo/KAGRA S230615az: Wendelstein observations of DESI galaxies and GIT candidates
  75. LIGO/Virgo S230620al: Global MASTER-Net observations report
  76. LIGO/Virgo S230620af: Global MASTER-Net observations report
  77. LIGO/Virgo S230620z: Global MASTER-Net observations report
  78. LIGO/Virgo S230620w: Global MASTER-Net observations report
  79. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  80. LIGO/Virgo S230620g: Global MASTER-Net observations report
  81. LIGO/Virgo S230619ay: Global MASTER-Net observations report
  82. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  83. ZTF23aaoohpy/AT2023lcr: OHP/T193 and OHP/T120 optical follow-up observations
  84. LIGO/Virgo S230619bd: Global MASTER-Net observations report
  85. LIGO/Virgo S230619bb: Global MASTER-Net observations report
  86. LIGO/Virgo S230619as: Global MASTER-Net observations report
  87. LIGO/Virgo S230619ap: Global MASTER-Net observations report
  88. ZTF23aaoohpy/AT2023lcr: GROWTH-India Telescope follow-up observations
  89. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  90. ZTF23aaoohpy/AT2023lcr: GOTO early optical observations and constraint
  91. ZTF23aaoohpy/AT2023lcr: Zwicky Transient Facility discovery of a fast fading red transient
  92. LIGO/Virgo S230619i: Global MASTER-Net observations report
  93. LIGO/Virgo/KAGRA S230615az: GRANDMA observations of GOTO and GIT candidates
  94. LIGO/Virgo S230619aa: Global MASTER-Net observations report
  95. LIGO/Virgo S230619x: Global MASTER-Net observations report
  96. LIGO/Virgo S230619e: Global MASTER-Net observations report
  97. LIGO/Virgo S230618at: Global MASTER-Net observations report
  98. LIGO/Virgo S230618ba: Global MASTER-Net observations report
  99. LIGO/Virgo S230618az: Global MASTER-Net observations report
  100. LIGO/Virgo S230618ae: Global MASTER-Net observations report

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