Expectations for time-delay measurements in active galactic nuclei with the Vera Rubin Observatory

Panda, Swayamtrupta; Prince, Raj; Jaiswal, Vikram Kumar; Aldama, Mary Loli Martinez; Kozłowski, S.; Kovačević, Andjelka; Ilić, D.; Núñez, F. Pozo; Hoenig, Sebastian; Brandt, W. N.

doi:10.48550/arxiv.2301.08975

Cited by 3 publications

(2 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As studied in Kovačević et al (2022), if the observational strategy for these fields has a cadence of 1-5 days and duration >9 yr, the expected number of sources, whose continuum lags can be successfully measured, is >1000 for each DDF (10 square degree) in any filter. Therefore, the DDFs will become ideal laboratories to measure CRM BH mass as well as investigate the possibility of disentangling the R BLR (Czerny et al 2023) and R CER through the photometric light curves.…”

Section: Discussionmentioning

confidence: 99%

Estimating AGN Black Hole Masses via Continuum Reverberation Mapping in the Era of LSST

Wang

Guo

Woo

2023

ApJL

View full text Add to dashboard Cite

Spectroscopic reverberation mapping (RM) is a direct approach widely used to determine the mass of black holes (BHs) in active galactic nuclei (AGNs). However, it is very time consuming and difficult to apply to a large AGN sample. The empirical relation between the broad-line region size and luminosity (Hβ R BLR–L) provides a practical alternative yet is subject to large scatter and systematic bias. Based on the relation between the continuum emitting region size and luminosity (R CER–L) reported by Netzer (2022), we present a new BH mass estimator via continuum RM (CRM) by comparing R CER and R BLR, assuming that the continuum lags are dominated by the diffuse continuum emission. Using a sample of 21 AGNs, we find a tight R BLR–R CER relation (scatter∼0.28 dex) and that R BLR is larger than R CER at 5100 Å by an average factor of 8.1. This tight relation enables the BH mass estimation based on the CRM combined with the velocity information. Applying the relation to rest objects in our CRM sample, we demonstrate that the predicted R BLR,CRM follows the existing Hβ R BLR–L relation well and the estimated CRM BH masses are consistent with the RM/single-epoch BH masses using Hβ. This method will provide significant applications for BH mass estimation thanks to the short continuum lags and the easily accessible high-cadence, large-area photometric data, especially in the era of Legacy Survey of Space and Time.

show abstract

Section: Discussionmentioning

confidence: 99%

Estimating AGN Black Hole Masses via Continuum Reverberation Mapping in the Era of LSST

Wang

Guo

Woo

2023

ApJL

View full text Add to dashboard Cite

show abstract

“…The bulk of objects have between 30 and 70 visits. For comparison, LSST sources will have a larger number of observations(Bianco et al 2022;Kovacevic et al 2022;Raiteri et al 2022;Czerny et al 2023;Pozo Nuñez et al 2023).…”

mentioning

confidence: 99%

The LSST AGN Data Challenge: Selection Methods

Savić

Jankov

et al. 2023

ApJ

View full text Add to dashboard Cite

Development of the Rubin Observatory Legacy Survey of Space and Time (LSST) includes a series of Data Challenges (DCs) arranged by various LSST Scientific Collaborations that are taking place during the project's preoperational phase. The AGN Science Collaboration Data Challenge (AGNSC-DC) is a partial prototype of the expected LSST data on active galactic nuclei (AGNs), aimed at validating machine learning approaches for AGN selection and characterization in large surveys like LSST. The AGNSC-DC took place in 2021, focusing on accuracy, robustness, and scalability. The training and the blinded data sets were constructed to mimic the future LSST release catalogs using the data from the Sloan Digital Sky Survey Stripe 82 region and the XMM-Newton Large Scale Structure Survey region. Data features were divided into astrometry, photometry, color, morphology, redshift, and class label with the addition of variability features and images. We present the results of four submitted solutions to DCs using both classical and machine learning methods. We systematically test the performance of supervised models (support vector machine, random forest, extreme gradient boosting, artificial neural network, convolutional neural network) and unsupervised ones (deep embedding clustering) when applied to the problem of classifying/clustering sources as stars, galaxies, or AGNs. We obtained classification accuracy of 97.5% for supervised models and clustering accuracy of 96.0% for unsupervised ones and 95.0% with a classic approach for a blinded data set. We find that variability features significantly improve the accuracy of the trained models, and correlation analysis among different bands enables a fast and inexpensive first-order selection of quasar candidates.

show abstract

Quasar UV/X-ray relation luminosity distances are shorter than reverberation-measured radius–luminosity relation luminosity distances

Khadka

Prince

Panda

et al. 2023

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We use measurements of 59/58 quasars (QSOs), over a redshift range 0.0041 ≤ z ≤ 1.686, to do a comparative study of the radius–luminosity (R − L) and X-ray−UV luminosity (LX − LUV) relations and the implication of these relations for cosmological parameter estimation. By simultaneously determining R − L or LX − LUV relation parameters and cosmological parameters in six different cosmological models, we find that both R − L and LX − LUV relations are standardizable but provide only weak cosmological parameter constraints, with LX − LUV relation data favoring larger current non-relativistic matter density parameter Ωm0 values than R − L relation data and most other available data. We derive LX − LUV and R − L luminosity distances for each of the sources in the six cosmological models and find that LX − LUV relation luminosity distances are shorter than R − L relation luminosity distances as well as standard flat ΛCDM model luminosity distances. This explains why LX − LUV relation QSO data favor larger Ωm0 values than do R − L relation QSO data or most other cosmological measurements. While our sample size is small and only spans a small z range, these results indicate that more work is needed to determine whether the LX − LUV relation can be used as a cosmological probe.

show abstract

Expectations for time-delay measurements in active galactic nuclei with the Vera Rubin Observatory

Cited by 3 publications

References 62 publications

Estimating AGN Black Hole Masses via Continuum Reverberation Mapping in the Era of LSST

Estimating AGN Black Hole Masses via Continuum Reverberation Mapping in the Era of LSST

The LSST AGN Data Challenge: Selection Methods

Quasar UV/X-ray relation luminosity distances are shorter than reverberation-measured radius–luminosity relation luminosity distances

Contact Info

Product

Resources

About