From maxiweb at maxi.riken.jp  Thu Jul  3 12:38:40 2025
From: maxiweb at maxi.riken.jp (maxiweb at maxi.riken.jp)
Date: Thu, 03 Jul 2025 12:38:40 +0900
Subject: [X-ray-star:972] Swift J1858.6-0814
Message-ID: <20250703033840.1B509611161A@maxi.riken.jp>

Brightening of Swift J1858.6-0814 (Y. Kawakubo)

=====================
MAXI transient alert
2025-07-02 14:35:59 UT
=====================

[Ground Trigger ID]
ID          :  858800020

[Count Weighted Position]
RA,Dec: (285.600,  -9.200)
Galac.: ( 25.955,  -6.607)
Eclip.: (285.835,  13.386)

[Triggered Criteria]

[Highest Significance]
DPTC  : 1435502086
UT    : 2025/07/02 14:35:59
on    : 1scan (Med-band)
sigma : 3.0

[Observed flux]
S :     45 +-    14 mCrab
L :     17 +-    15 mCrab
M :     82 +-    27 mCrab
H :    192 +-    93 mCrab

nearby(r<5deg) object
=====================
dist  flux  (RA, Dec)        name
[deg][mCrab]  [deg]
=====================
1.35      1.7 (284.64,  -8.24)  Swift J1858.6-0814
2.35      4.8 (283.27,  -8.71)  4U 1850-086,H 1850-087
3.94     -2.8 (287.58,  -5.79)  MAXI J1910-057,Swift J1910.2-0546
4.88  unknown (280.94,  -7.61)  V496 Sct

[Sun/Moon (RA, Dec)]
Sun :  (101.547, 23.021)
Moon:  (187.045, -4.715)
age: 6.87 day

[Longitude/Latitude]
(100.32E, 11.82N)


We will report more detailed information on this event to ATel and/or GCN.

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For more information:
 http://maxi.riken.jp/alert/novae/0858800020/0858800020.htm

About MAXI data:
 http://maxi.riken.jp/