ETC Request ID: STIS.sp.918694

Requested Signal/Noise Ratio = 100.000 at wavelength 3000.00 Å (per resolution element)

gives: Time = 2,316.0216 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: Buffer time 39.1985 is less than minimum 99 seconds.


Table of Source and Noise Counts per Pixel

Plots

Detailed Information Count rate Total counts Associated noise
(counts/s) (counts) (counts)
Counts (box 7 pixels high) (1 pix x pix) (2.0 pix resel x pix)
    Source 2.241 10,380.85 101.89
    Background 0.011 48.64 6.97
        Sky 2.950e-09 1.37e-05 3.70e-03
        Dark Current 0.011 48.64 6.97
Total in selected region 2.252 10,429.48 103.81
Brightest Pixel (single exposure) (at 2879.59 Å) 1.208 2,798.80
Count rate entire detector 51,022.399
Buffer Time (sec) 39.20
For APT purposes, the recommended buffer time should be 4/5 of the buffer time calculated above. Please refer to the STIS Instrument Handbook for more details.
Global Count Rates
    Source only 47,410.880 109,804,619.441
    Background (sky+dark) 1,572.864 3,642,787.12
Encircled energy fraction 0.93

Instrument name: STIS
Mode: spectroscopic
Detector: NUVMAMA
Central Wavelength: 3012
Grating: [E230H] R ~ 114000
Aperture: 0.2X0.09


Target: [point source]
Spectrum: Flat in units of Fλ
Extinction E(B-V): None
Normalization: Flux 1.6e-11 flam at 3000.0 Å
Redshift: None
Emission Lines: None


Selected background:
  Sky Background:
    Level:

Table of Source and Noise Counts per Pixel

Plots

These results were computed using: ETC version 25.1.1