[A New Redshift Measuring Method for Low-Quality Galaxy Spectra Based on Multi Resolution Fusion Distance].

Area of Science:

• Astronomy and Astrophysics
• Cosmology
• Spectroscopy

Background:

• Accurate redshift measurement is vital for large astronomical spectral surveys to determine galaxy distances.
• Increasingly distant and faint galaxies in extragalactic surveys yield low-quality spectra.
• Existing methods struggle with poor spectral quality, necessitating new approaches for redshift determination.

Purpose of the Study:

• To develop and evaluate a novel method for accurate redshift measurement from low-quality galaxy spectra.
• To address the challenges posed by faint objects and poor spectral data in large-scale astronomical surveys.
• To improve the efficiency and accuracy of redshift determination for extragalactic targets.

Main Methods:

• A new multi-resolution fusion distance is defined for low-quality spectra.
• The method combines spectral features across different resolutions.
• Template and target spectra are aligned, and a weighted average of distances across resolutions is computed.

Main Results:

• The proposed method achieves over 90% accuracy for signal-to-noise ratios greater than 5.
• Measuring error is independent of the redshift value.
• Experiments demonstrate high efficiency in measuring redshifts from low-quality galaxy spectra.

Conclusions:

• The novel multi-resolution fusion distance method is effective for low-quality galaxy spectra.
• This technique is suitable for large-scale astronomical surveys requiring accurate redshift measurements.
• The method offers a robust solution for analyzing faint and distant extragalactic objects.