KnownObjectsMetric

class rubin_sim.maf.metrics.KnownObjectsMetric(elong_thresh=100.0, v_mag_thresh1=20.0, eff1=0.1, t_switch1=53371, v_mag_thresh2=21.5, eff2=0.1, t_switch2=57023, v_mag_thresh3=22.0, eff3=0.1, t_switch3=59580, v_mag_thresh4=22.0, eff4=0.2, elong_col='Elongation', mjd_col='MJD(UTC)', **kwargs)

Bases: BaseMoMetric

Identify SSobjects which could be classified as ‘previously known’ based on their peak V magnitude. This is most appropriate for NEO surveys, where most of the sky has been covered so the exact location (beyond being in the visible sky) is not as important.

Default parameters tuned to match NEO survey capabilities. Returns the time at which each first reached that threshold V magnitude. The default values are calibrated using the NEOs larger than 140m discovered in the last 20 years and assuming a 30% completeness in 2017.

Parameters:

elong_threshfloat, optional

The cutoff in solar elongation to consider an object ‘visible’. Default 100 deg.

v_mag_thresh1float, optional

The magnitude threshold for previously known objects. Default 20.0.

eff1float, optional

The likelihood of actually achieving each individual input observation. If the input observations include one observation per day, an ‘eff’ value of 0.3 would mean that (on average) only one third of these observations would be achieved. This is similar to the level for LSST, which can cover the visible sky every 3-4 days. Default 0.1

t_switch1float, optional

The (MJD) time to switch between v_mag_thresh1 + eff1 to v_mag_thresh2 + eff2, e.g. the end of the first period. Default 53371 (2005).

v_mag_thresh2float, optional

The magnitude threshhold for previously known objects. Default 22.0. This is based on assuming PS and other surveys will be efficient down to V=22.

eff2float, optional

The efficiency of observations during the second period of time. Default 0.1

t_switch2float, optional

The (MJD) time to switch between v_mag_thresh2 + eff2 to v_mag_thresh3 + eff3. Default 57023 (2015).

v_mag_thresh3float, optional

The magnitude threshold during the third period. Default 22.0, based on PS1 + Catalina.

eff3float, optional

The efficiency of observations during the third period. Default 0.1

t_switch3float, optional

The (MJD) time to switch between v_mag_thresh3 + eff3 to v_mag_thresh4 + eff4. Default 59580 (2022).

v_mag_thresh4float, optional

The magnitude threshhold during the fourth (last) period. Default 22.0, based on PS1 + Catalina.

eff4float, optional

The efficiency of observations during the fourth (last) period. Default 0.2

Methods Summary

run(sso_obs, orb, hval)

Calculate the metric value.

Methods Documentation

run(sso_obs, orb, hval)

Calculate the metric value.

Parameters:

sso_obs: np.ndarray

The input data to the metric (same as the parent metric).

orb: np.ndarray

The information about the orbit for which the metric is being calculated.

hvalfloat

The H value for which the metric is being calculated.

Returns:

float or np.ndarray or dict