LFAST ETC

Instrument

Preset

Overrides (blank = preset value)

Resolving power Pixels / resel

Spectrograph eff. Slit throughput QE

Read noise (e-) Dark (e-/s/pix)

Telescope array

N telescopes Fiber Combine

Source

Type Teff (K) Alpha (F_nu ~ nu^a)

Magnitude Band System

Calculation

Mode

Target SNR / resel Exposure time (s) N exposures

λ min (nm) λ max (nm)

{% if error %}

Input error: {{ error }}

{% endif %} {% if summary %}

Summary

{% for p in ("10", "50", "90") %}{% endfor %} {% for p in ("10", "50", "90") %}{% endfor %}

	10%	50%	90%
Exposure time (s){% if mode_label == "exptime" %} — solved{% endif %}	{% if summary.exptime[p] is none %}n/a{% else %}{{ "%.4g"\|format(summary.exptime[p]) }}{% endif %}
SNR per resel{% if mode_label == "snr" %} — solved{% endif %}	{% if summary.snr[p] is none %}n/a{% else %}{{ "%.4g"\|format(summary.snr[p]) }}{% endif %}
Saturated bins	{{ "%.1f"\|format(100 * summary.saturated_fraction) }}%
Reads shorter than the instrument minimum	{{ "%.1f"\|format(100 * summary.below_min_exptime_fraction) }}%
Bins with zero throughput (telluric cores, NaN)	{{ "%.1f"\|format(100 * summary.nan_fraction) }}%
Wavelength bins	{{ summary.n_bins }}
Limiting {{ summary.limiting_mag_band }} mag ({{ summary.limiting_mag_system }}), SNR=10 in 1 hr	{% if summary.limiting_mag_snr10_1hr is none %}n/a{% else %}{{ "%.2f"\|format(summary.limiting_mag_snr10_1hr) }}{% endif %}

{{ describe }}

{% if plot_note %}

{% endif %} {% for d in plot_divs %}

{% endfor %} {{ plot_script|safe }} {% elif not error %}

Set up the instrument, array and source on the left, then press Calculate.

{% endif %}