Gauribidanur Low-Frequency Solar Spectrograph

LOTUS: a low-cost, ultraviolet spectrograph

We describe the design, construction and commissioning of a simple, low-cost long-slit spectrograph for the Liverpool Telescope. The design is optimized for near-UV and visible wavelengths and uses all transmitting optics. It exploits the instrument focal plane field curvature to partially correct axial chromatic aberration. A stepped slit provides narrow (2.5 × 95 arcsec) and wide (5× 25 arcse...

Astro2010: Solar and Heliospheric Physics with Low Frequency Radio Arrays

Solar activity cycle frequency shifts of low-degree p-modes

We report on an extensive analysis of the low-degree p-mode frequency shifts over Solar Cycle n ̄ 22 (1984–1995) based on continuous data taken at the Observatorio del Teide (Tenerife). Aside from the known good correlation between frequency shifts and solar activity indices, we have also investigated on short and long time-scales correlations (from 2months to 1.5 years and from 1.5 to 11 years)...

The visibility of low-frequency solar acoustic modes

We make predictions of the detectability of low-frequency p modes. Estimates of the powers and damping times of these low-frequency modes are found by extrapolating the observed powers and widths of higher-frequency modes with large observed signal-to-noise ratios. The extrapolations predict that the low-frequency modes will have small signal-to-noise ratios and narrow widths in a frequency-pow...

The Hobby-Eberly Telescope Low Resolution Spectrograph: optical design

The Hobby Eberly Telescope (HET) is a revolutionary large telescope of 9.2 meter aperture, which is currently undergoing commissioning at McDonald Observatory. First light was obtained on December 11, 1996. Scientific operations are expected in 1998. The Low Resolution Spectrograph (LRS, a collaboration between the University of Texas at Austin, the Instituto de Astronomía de la Universidad Nac...