TITLE: GCN CIRCULAR NUMBER: 35499 SUBJECT: IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources DATE: 24/01/08 17:04:31 GMT FROM: Kuiyun Huang at CYCU <kuiyun@gmail.com> K.Y. Huang and Y. Urata, on behalf of a large collaboration SCUBA2 onboard JCMT captured images in 450um and 850um encompassing the entire 90% PSF containment region of IceCube-240105A (GCN Circ. #35485) on January 6, 2024. No sources with an rms of 7 mJy were detected within the 90% PSF containment region of IceCube-240105A. However, the 850μm map revealed the presence of two bright sources near the periphery of the 90% PSF containment region. These sources are identified as PKS 0446+11 and the flat spectrum radio quasar (or Blazar, hereafter J0448+1127), previously cataloged in various publications. SCUBA2 measured the peak flux for PKS 0446+11 as 1130 mJy at 850um 838 mJy at 450um Combined with the ALMA calibrator source catalog, the light curve peaked on November 5, 2023. The SCUBA2 measurement indicates a slight fading from the peak. The other source, J0448+1127, is located at 04:49:07.754 +11:21:31 with 13 arcsec error, 0.48 deg away from the IceCube's best-fit position. Catalog matching indicates the source is FSRQ, with redshift 1.375 recorded in various catalogs. SCUBA2 measured the peak flux as 104 mJy at 850um. Although there are no suitable reference observations for variability checking, the source may exhibit brightening based on comparisons with the last observation by ALMA in 2021 with a similar wavelength. View this GCN Circular online at https://gcn.nasa.gov/circulars/35499. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...