Beyond lecture capture: What teaching staff want from web-based lecture technologies

For the past decade, the primary use of recordings in higher education has been to make live lectures available to students for review (lecture capture). However, with the rise of podcasting and the increased focus on interaction as a means to engage students, current web-based lecture technologies (WBLT) are capable of much more than simply recording and distributing a live lecture. This study aimed to discover what teaching staff are currently doing, and what they would like to be doing with WBLT for learning and teaching. Data were drawn from initial focus groups conducted with 10 academic teaching staff at Swinburne University of Technology, as well as an online survey that was distributed to all Swinburne staff with a lecture capture account. Three key requirements for a university-wide WBLT system were identified: flexibility in where and when recordings can be made, flexibility in control over those recordings, and the desire to be able to interact with the recordings and incorporate them as an integral part of the course. These findings indicate that teaching staff want to innovate in their use of recordings and need to be supported to do so through the adoption of an appropriate recording solution

An Atlas of Spectrophotometric Landolt Standard Stars

We present CCD observations of 102 Landolt standard stars obtained with the R-C spectrograph on the CTIO 1.5 m telescope. Using stellar atmosphere models we have extended the flux points to our six spectrophotometric secondary standards, in both the blue and the red, allowing us to produce flux-calibrated spectra that span a wavelength range from 3050 \AA to 1.1 \micron. Mean differences between UBVRI spectrophotometry computed using Bessell's standard passbands and Landolt's published photometry is found to be 1% or less. Observers in both hemispheres will find these spectra useful for flux-calibrating spectra and through the use of accurately constructed instrumental passbands be able to compute accurate corrections to bring instrumental magnitudes to any desired standard photometric system (S-corrections). In addition, by combining empirical and modeled spectra of the Sun, Sirius and Vega, we calculate and compare synthetic photometry to observed photometry taken from the literature for these three stars.Comment: Added referee's comments, minor corrections, replaced Table 1

SN1997cy/GRB970514 - A New Piece in the GRB Puzzle?

We present observations of SN1997cy, a supernova discovered as part of the Mount Stromlo Abell Cluster SN Search, which does not easily fit into the traditional classification scheme for supernovae. This object's extraordinary optical properties and coincidence with GRB970514, a short duration gamma ray burst, suggest a second case, after SN1998bw/GRB980425, for a SN-GRB association. SN1997cy is among the most luminous SNe yet discovered and has a peculiar spectrum. We present evidence that SN1997cy ejected approximately 2 solar masses of 56Ni, supported by its late-time light curve, and FeII/[FeIII] lines in its spectrum, although it is possible that both these observations can be explained via circumstellar interaction. While SN1998bw and SN1997cy appear to be very different objects with respect to both their gamma ray and optical properties, SN1997cy and the optical transient associated with GRB970508 have roughly similar late-time optical behavior. This similarity may indicate that the late-time optical output of these two intrinsically bright transient events have a common physical process. Although the connection between GRB970514 and SN1997cy is suggestive, it is not conclusive. However, if this association is real, followup of short duration GRBs detected with BATSE or HETE2 should reveal objects similar to SN1997cy.Comment: 26 pages including 6 postscript figures and 3 tables. Submitted to ApJ. Re-calibrated photometry - objects are about 0.3mags brighter than in original versio

The Mount Stromlo Abell Cluster Supernova Search

We have initiated a three-year project to find supernovae (SNe) in a well-defined sample of high-density southern Abell clusters with redshifts $z\leq0.08$. These observations will provide a volume-limited sample of SNe Ia to more than a magnitude below their peak brightness, and will enable us to: (1) measure the luminosity function of SNe, (2) further explore the correlation of light curve shape with the absolute luminosity of SNe Ia to better understand SNe Ia as distance indicators, (3) measure SN rates, (4) measure the bulk motion of the Local Group using SNe Ia, and (5) directly compare SN Ia distances to brightest cluster galaxy distances. We use the MaCHO wide-field 2-color imager on the 1.3m telescope at Mount Stromlo to routinely monitor $\sim 12$ clusters per week. We describe our technique for target selection and scheduling search observations, and for finding and identifying SN candidates. We also describe the results from the first year of our program, including the detection of 19 SNe, several RR-Lyrae variables, and hundreds of asteroids.Comment: 20 pages, 10 figures, 3 tables. Accepted for publication in AJ, Jan. 1998 issu

Hubble Space Telescope and Ground-Based Observations of Type Ia Supernovae at Redshift 0.5: Cosmological Implications

We present observations of the Type Ia supernovae (SNe) 1999M, 1999N, 1999Q, 1999S, and 1999U, at redshift z~0.5. They were discovered in early 1999 with the 4.0~m Blanco telescope at Cerro Tololo Inter-American Observatory by the High-z Supernova Search Team (HZT) and subsequently followed with many ground-based telescopes. SNe 1999Q and 1999U were also observed with the Hubble Space Telescope. We computed luminosity distances to the new SNe using two methods, and added them to the high-z Hubble diagram that the HZT has been constructing since 1995. The new distance moduli confirm the results of previous work. At z~0.5, luminosity distances are larger than those expected for an empty universe, implying that a ``Cosmological Constant,'' or another form of ``dark energy,'' has been increasing the expansion rate of the Universe during the last few billion years.Comment: 68 pages, 22 figures. Scheduled for the 01 February 2006 issue of Ap.J. (v637

Optical and Near-Infrared Observations of the Peculiar Type Ia Supernova 1999ac

We present 39 nights of optical photometry, 34 nights of infrared photometry, and 4 nights of optical spectroscopy of the Type Ia SN 1999ac. This supernova was discovered two weeks before maximum light, and observations were begun shortly thereafter. At early times its spectra resembled the unusual SN 1999aa and were characterized by very high velocities in the Ca II H and K lines, but very low velocities in the Si II 6355 A line. The optical photometry showed a slow rise to peak brightness but, quite peculiarly, was followed by a more rapid decline from maximum. Thus, the B- and V-band light curves cannot be characterized by a single stretch factor. We argue that the best measure of the nature of this object is not the decline rate parameter Delta m_15 (B). The B-V colors were unusual from 30 to 90 days after maximum light in that they evolved to bluer values at a much slower rate than normal Type Ia supernovae. The spectra and bolometric light curve indicate that this event was similar to the spectroscopically peculiar slow decliner SN 1999aa.Comment: 42 pages, 14 figures, accepted for publication in the Astronomical Journal (January 28, 2006

Optical and Infrared Photometry of the Nearby Type Ia Supernovae 1999ee, 2000bh, 2000ca, and 2001ba

We present near infrared photometry of the Type Ia supernova 1999ee; also, optical and infrared photometry of the Type Ia SNe 2000bh, 2000ca, and 2001ba. For SNe 1999ee and 2000bh we present the first-ever SN photometry at 1.035 microns (the Y-band). We present K-corrections which transform the infrared photometry in the observer's frame to the supernova rest frame. Using our infrared K-corrections and stretch factors derived from optical photometry, we construct JHK templates which can be used to determine the apparent magnitudes at maximum if one has some data in the window -12 to +10 d with respect to T(B_max). Following up previous work on the uniformity of V minus IR loci of Type Ia supernovae of mid-range decline rates, we present unreddened loci for slow decliners. We also discuss evidence for a continuous change of color at a given epoch as a function of decline rate.Comment: 53 pages, 14 figures, to be published in the March 2004 issue of the Astronomical Journa

The Most Slowly Declining Type Ia Supernova 2001ay

We present optical and near-infrared photometry, as well as ground-based optical spectra and Hubble Space Telescope ultraviolet spectra, of the Type Ia supernova (SN) 2001ay. At maximum light the Si II and Mg II lines indicated expansion velocities of 14,000 km/sec, while Si III and S II showed velocities of 9,000 km/sec There is also evidence for some unburned carbon at 12,000 km/sec. SN 2001ay exhibited a decline-rate parameter Delta m_15(B) = 0.68 \pm 0.05 mag; this and the B-band photometry at t > +25 d past maximum make it the most slowly declining Type Ia SN yet discovered. Three of four super-Chandrasekhar-mass candidates have decline rates almost as slow as this. After correction for Galactic and host-galaxy extinction, SN 2001ay had M_B = -19.19 and M_V = -19.17 mag at maximum light; thus, it was not overluminous in optical bands. In near-infrared bands it was overluminous only at the 2-sigma level at most. For a rise time of 18 d (explosion to bolometric maximum) the implied Ni-56 yield was (0.58 \pm 0.15)/alpha M_Sun, with alpha = L_max/E_Ni probably in the range 1.0 to 1.2. The Ni-56 yield is comparable to that of many Type Ia supernovae. The "normal" Ni-56 yield and the typical peak optical brightness suggest that the very broad optical light curve is explained by the trapping of the gamma rays in the inner regions.Comment: 57 pages, 22 figures. To be published in the Astronomical Journal (September 2011