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We assemble a catalogue of 488 spectroscopically confirmed very high ($zgeq5.00$) redshift quasars and report their near- ($ZYJHK_{s}/K$) and mid- (WISE W1234) infrared properties. 97% of the VH$z$Q sample is detected in one or more NIR ($ZYJHK/K_{s}$) band, with lack of coverage rather than lack of depth being the reason for the non-detections. 389 (80%) of the very high redshift quasars are detected at 3.4$mu$m in the W1 band from the unWISE catalog and all of the $zgeq7$ quasars are detected in both unWISE W1 and W2. Using archival WFCAM/UKIRT and VIRCAM/VISTA data we check for photometric variability that might be expected from super-Eddington accretion. We find 28 of the quasars have sufficient NIR measurements and signal-to-noise ratio to look for variability. Weak variability was detected in multiple bands of SDSS J0959+0227, and very marginally in the $Y$-band of MMT J0215-0529. Only one quasar, SDSS J0349+0034, shows significant differences between WFCAM and VISTA magnitudes in one band. With supermassive black hole accretion likely to be redshift invariant up to very high-redshift, further monitoring of these sources is warranted. All the data, analysis codes and plots used and generated here can be found at: https://github.com/d80b2t/VHzQ}{tt github.com/d80b2t/VHzQ.
We analyse a sample of 85 luminous (log(nuLnu(3um)/erg s-1)>45.5) quasars with restframe ~2-11 um spectroscopy from AKARI and Spitzer. Their high luminosity allows a direct determination of the near-infrared quasar spectrum free from host galaxy emis
We present mid-infrared spectra of six FeLoBAL QSOs at 1<z<1.8, taken with the Spitzer space telescope. The spectra span a range of shapes, from hot dust dominated AGN with silicate emission at 9.7 microns, to moderately obscured starbursts with stro
We present Spitzer InfraRed Spectrograph (IRS) low-resolution spectra of 16 spectroscopically selected post-starburst quasars (PSQs) at z ~ 0.3. The optical spectra of these broad-lined active galactic nuclei (AGNs) simultaneously show spectral signa
We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope. The MIR properties of IR QSOs are
We discuss color selection of rare objects in a wide-field, multiband survey spanning from the optical to the mid-infrared. Simple color criteria simultaneously identify and distinguish two of the most sought after astrophysical sources: the coolest