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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"

21018 results found.

  1. LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
  2. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  3. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  4. GRB 170830A: iTelescope optical observations
  5. LIGO/Virgo G298048: European VLBI Network (EVN) upper limit on 5 GHz compact emission from SSS17a
  6. LIGO/Virgo G299232: SVOM/2.16-m Optical Telescope Observations of Swift UVOT Transient
  7. LIGO/Virgo G298048: OVRO 40m telescope follow-up
  8. LIGO/Virgo G299232: HAWC follow-up
  9. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  10. LIGO/Virgo G299232 : RATIR Optical and NIR Observations of Swift UVOT source
  11. LIGO/Virgo G299232: Liverpool Telescope observations
  12. LIGO/Virgo G299232: observations of the optical Transient Discovered by Swift/UVOT
  13. LIGO/Virgo G299232: PIRATE observations of MASTER OT J033744.97+723159.0
  14. LIGO/Virgo G299232/PGWB170825.55: early MASTER observations of the Swift UVOT source position
  15. LIGO/Virgo G296853: PIRATE observations
  16. LIGO/Virgo G298048: ALMA observations
  17. LIGO/Virgo G298048: Konus-Wind observations
  18. LIGO/Virgo G299232: GRAWITA Asiago/Copernico Telescope observations
  19. LIGO/Virgo G298048: Zadko Telescope 7 day observations of the OT candidate SSS17a/DLT17ck
  20. GRB170827A: Further GROND follow-up observations
  21. LIGO/Virgo G299232: COATLI Observations of MASTER OT J033744.97+723159.0
  22. LIGO/Virgo G299232 : MAXI/GSC observations
  23. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  24. LIGO/Virgo G299232: Continued observation of the transient near NGC 1343
  25. LIGO/Virgo G299232/PGWB170825.55: MASTER OT J033744.97+723159.0 inside 25m isophota of the NGC1343 galaxy is reddening
  26. LIGO/Virgo G299232: Optical Transient Discovery by Swift/UVOT
  27. LIGO/Virgo G299232 TZAC/TAROT observations
  28. GROND observations of GRB170827A
  29. GRB 170827A: ePESSTO NTT afterglow candidate
  30. GRB 170823A: TAROT Calern observatory optical observations
  31. LIGO/Virgo G299232: OVRO-LWA simultaneous low frequency radio observations of localization region
  32. LIGO/Virgo G299232: LOFAR follow-up
  33. GRB 170827A: Swift/UVOT Upper Limits
  34. GRB 170827A: REM optical/NIR observations
  35. LIGO/Virgo G299232/PGWB170825.55: MASTER OTJ033744.97+723159.0 off set from NGC1343 galaxy
  36. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  37. LIGO/Virgo G299232: CALET Observations
  38. LIGO/VIRGO G299232: Fermi GBM Observations
  39. LIGO/Virgo G299232 : Fermi-LAT search for high-energy gamma-ray counterpart
  40. LIGO/Virgo G298048: uGMRT Follow-up of SSS17a at 400 MHz and 1.4 GHz
  41. LIGO/Virgo G298936: CALET Observations
  42. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  43. LIGO/Virgo G299232: AGILE GRID observations
  44. LIGO/Virgo G299232: INTEGRAL search for a prompt gamma-ray counterpart
  45. LIGO/Virgo G296853: VLT observations by GLGW Hunters
  46. LIGO/Virgo G297595: INTEGRAL pointed follow-up observations
  47. LIGO/Virgo G297595: Gemini and VLT observations by GLGW Hunters
  48. LIGO/Virgo G298936 TAROT/TZAC observations
  49. LIGO/Virgo G298936 : MAXI/GSC observations
  50. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  51. LIGO/Virgo G298048: Subaru HSC z-band imaging of the OT candidate SSS17a
  52. LIGO/Virgo G298048: Near-infrared fading from Gemini-South
  53. LIGO/Virgo G298048: HAWC follow-up
  54. LIGO/Virgo G298048: Gemini-South Imaging and Spectroscopy
  55. LIGO/Virgo G298048: MUSE Integral Field Observations
  56. LIGO/Virgo G298048: LWA radio observations
  57. LIGO/VIRGO G298048: AAT/AAO spectroscopic observations of the GW counterpart candidate SSS17a/DLT17ck
  58. LIGO/Virgo G298048: LOFAR follow-up
  59. LIGO/Virgo G298936: GWFUNC/CNEOST optical observations and an optical transient
  60. LIGO/Virgo G298048: H.E.S.S. very-high energy gamma-ray follow-up
  61. LIGO/Virgo G297595: H.E.S.S. very-high energy gamma-ray follow-up
  62. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  63. LIGO/Virgo G298048: Results of the ASKAP search for fast radio bursts
  64. LIGO/Virgo G298048: ATCA follow-up of SSS17a in NGC 4993
  65. LIGO/Virgo G298389: CALET Observations
  66. LIGO/Virgo G298048: Continued VLA monitoring at 6 GHz
  67. LIGO/VIRGO G298936: Fermi GBM Observations
  68. LIGO/Virgo G298936: AGILE GRID observations
  69. LIGO/Virgo G298936: AGILE MCAL observations
  70. LIGO/Virgo G298936: INTEGRAL was inactive at the time of the event
  71. LIGO/Virgo G298936: IceCube neutrino observations
  72. GRB 170822A: RATIR Optical and NIR Observations
  73. LIGO/Virgo G298048: ESO/VLT optical observations
  74. LIGO/VIRGO G298048: VLA/JAGWAR observations of the CLU galaxies
  75. GRB 170822A: Swift/UVOT Upper Limits
  76. LIGO/Virgo G298048: Chandra X-ray observations
  77. LIGO/Virgo G298389 : MAXI/GSC observations
  78. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  79. GRB 170822A:BOOTES-5/JGT optical afterglow candidate
  80. LIGO/Virgo G298048: CALET Observations
  81. LIGO/Virgo G298048: ASKAP observations of SSS17a and NGC 4993 at 1.345 GHz
  82. LIGO/Virgo G298048: Gemini-South Near-Infrared Spectroscopy
  83. LIGO/Virgo G298048: MWA Observations of Error Region
  84. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  85. LIGO/Virgo G298048: TOROS Spectra observation with CASLEO
  86. LIGO/Virgo G298048: Pan-STARRS izy photometry of SSS17a/DLT17ck
  87. LIGO/Virgo G298048: Continued monitoring of the optical counterpart candidate
  88. LIGO/Virgo G298048: Correction to ATCA 8.5 GHz observations
  89. LIGO/Virgo G298048: ATCA 8.5 GHz observations of galaxies in the localisation volume
  90. LIGO/Virgo G298048: Zadko observations of the OT candidate SSS17a/DLT17ck
  91. LIGO/Virgo G298048: NuSTAR limits on X-ray emission
  92. LIGO/Virgo G298048: ASKAP follow up
  93. LIGO/Virgo G298048: optical observations with BOOTES-5 at San Pedro Mártir
  94. LIGO/Virgo G298048: TOROS optical counterpart search (continuation)
  95. LIGO/Virgo G298048: TOROS optical counterpart search
  96. LIGO/Virgo G298048: optical observations of CHILESCOPE observatory
  97. LIGO/Virgo G298048: Pan-STARRS izy photometry monitoring of SSS17a/DLT17ck
  98. LIGO/Virgo G298048: Continued VLA observations
  99. LIGO/Virgo G298048: Possible X-ray detection with Swift
  100. LIGO/Virgo G298389: INTEGRAL search for a prompt gamma-ray counterpart

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