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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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subject:"Swift"
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submitter:"Judith Racusin"

21947 results found.

  1. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  2. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  3. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  4. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  5. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  6. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  7. Konus-Wind detection of GRB 241115D / EP 241115a
  8. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  9. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  10. GRB 241026A: radio detection with the VLA
  11. EP241125a: Optical upper limit with Kinder observations
  12. EP241125a: EP detection of an X-ray transient
  13. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  14. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  15. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  16. GRB 241120A: GRBAlpha detection
  17. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  18. Konus-Wind detection of GRB 241117A
  19. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  20. IPN triangulation of GRB 241117A
  21. GRB 241026A: VIRT Optical Upper Limit
  22. GRB 241025A: VIRT Optical Upper Limit
  23. GRB241120A: OHP/T193 optical observations
  24. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  25. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  26. GRB 241120A: Mondy and AbAO optical observations
  27. EP241119a: Optical upper limits with Kinder observations
  28. EP trigger ID 01709122294: the X-ray transient is likely a stellar flare event
  29. EP241119a: GIT optical upper limits
  30. EP241119a : J-band observations with WINTER
  31. EP241119a: EP detection of a fast X-ray transient
  32. GRB 241112B: Mephisto further optical observations
  33. GRB 241030A: J-band observations
  34. GRB 241115a: PRIME near-infrared upper limits
  35. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  36. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  37. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  38. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  39. GRB 241115A: Swift-XRT afterglow detection
  40. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  41. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  42. GRB 241115A: Mephisto upper limits
  43. GRB 241113B: Mephisto upper limits
  44. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  45. GRB 241115D / EP 241115a: SVOM/GRM observation
  46. EP241113a: Swift XRT weak detection
  47. GRB 241115A: LCOGT Optical Upper Limits
  48. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  49. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  50. EP241115a: EP detection of a fast X-ray transient
  51. Swift GRB 241115A: Global MASTER-Net observations report
  52. Fermi GRB 241115A: Global MASTER-Net observations report
  53. GRB 241115A: Swift detection of a burst
  54. EP 241113a: LBT possible optical counterpart
  55. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  56. GRB 241113A: PRIME near-infrared upper limits
  57. GRB 241113B: J-band upper limit from WINTER
  58. GRB 241113A: J-band observations with WINTER
  59. EP241113a : J-band observations with WINTER
  60. GRB 241030A: LCO optical observation
  61. GRB 241113B: Swift-XRT observations
  62. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  63. EP241113b/GRB 241113B: EP detection of GRB 241113B
  64. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  65. GRB 241113A: Swift/UVOT Detection
  66. GRB 241113A: REM detection of the optical/NIR afterglow
  67. Konus-Wind detection of GRB 241107A (short/hard)
  68. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  69. GRB 241113A: LCO optical observations
  70. GRB 241112B: GMG Optical Upper Limit
  71. GRB 241113A: Enhanced Swift-XRT position
  72. GRB241113A: LCOGT (40-cm) optical counterpart detection
  73. GRB 241113A: Swift detection of a burst with an optical counterpart
  74. SVOM/GRM detection of a short burst from SGR 1E1841-045
  75. Fermi trigger No 753166198: Global MASTER-Net observations report
  76. GRB 241112B: AbAO optical upper limit
  77. GRB 241107A: GROWTH-India telescope optical upper limit
  78. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  79. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  80. GRB 241112B: Mephisto optical upper limits
  81. GRB 241112B: GOTO optical upper limits
  82. GRB 241107A: INTEGRAL IBIS localization
  83. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  84. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  85. IPN triangulation of GRB 241107A (short/hard)
  86. GRB 241025C: VZLUSAT-2 detection
  87. GRB 241025A: VZLUSAT-2 detection
  88. GRB 241018A: cubesat Avion detection
  89. GRB 241030B: TESS detection of optical counterpart
  90. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  91. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  92. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  93. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  94. EP241107a: AbAO optical upper limit
  95. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  96. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  97. EP241109a: confirmation of a stellar flare by BOOTES-7
  98. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  99. EP241107a: KAIT optical observations
  100. GRB 241030A: TESS observations

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