ETC Request ID: STIS.sp.1046486

Requested Signal/Noise Ratio = 10.000 at wavelength 2850.00 Å (per resolution element)

gives: Time = 21.3811 seconds

gives: Time to Saturation (for a single exposure) = 2,570.13 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.19) is less than the recommended threshold of 20 electrons to avoid poor charge transfer efficiency (CTE). We suggest you consider CTE mitigation strategies described in the STIS Instrument Handbook."


Table of Source and Noise Counts per Pixel


Plots


Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (box 7 pixels high) (1 pix x 7 pix) (2 pix resel x 7 pix)
    Source 8.949 382.67 19.56
    Background 0.126 5.39 2.32
        Sky 3.962e-06 1.69e-04 0.01
        Dark Current 0.126 5.39 2.32
    Read Out 32.81
Total in selected region 9.075 388.06 38.27
Brightest Pixel (single exposure) (at 3065.10 Å) 12.840 137.26

Global Count Rates
    Source only 5,081.149 108,640.354
    Background (sky+dark) 18,879.489 403,663.45

Encircled energy fraction 0.95


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G230LB] R ~ 700
Aperture: 52X0.2
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: Black body at 3700.0K
Extinction E(B-V): None
Normalization: Renormalized to vegamag = 10.3 in filter Johnson/U
Redshift: None
Emission Lines:
Line at Center 2796.0 Å    FWHM 1.6 Å   Flux 2.75e-13 Fλ


Selected background:
  Sky Background:
    Level:

Table of Source and Noise Counts per Pixel


Plots

These results were computed using: ETC version 25.2