X-ray spectrum of the high polarization quasar PKS 1510-089

We present results on the X-ray spectra of the radio-loud, high-polarization quasar, PKS 1510-089, based on new data obtained using ASCA, and from archival ROSAT data. The X-ray spectrum obtained by ASCA is unusually hard, with the photon index=1.30+-0.06, while the (non-simultaneous) ROSAT data indicate a steeper spectrum (1.9+-0.3). The X-ray flux at 1 keV is within 10% during both observations. A break in the underlying continuum at about 0.7 keV is suggested. Flat X-ray spectra seem to be the characteristic of high polarization quasars, and their spectra also appear to be harder than that of the other radio-loud but low-polarization quasars. The multiwavelength spectrum of PKS 1510-089 is similar to many other gamma-ray blazars, suggesting the emission is dominated by that from a relativistic jet. A big blue-bump is also seen in its multiwavelength spectrum, suggesting the presence of a strong thermal component as well.Comment: 19 pages (Latex + 5 ps figures), Accpeted for publication in the Astrophysical Journal, December 20, 199

The ultraviolet spectrum of the magnetic cataclysmic variable RX J1802.1+1804

We observed the counterpart to the X-ray source RX J1802.1+1804, an object recently discovered as part of a survey to identify the optical counterparts to ultrasoft X-ray sources in the ROSAT point-source catalog that was subsequently identified as a magnetic cataclysmic variable, with the ultraviolet spectrometers on IUE in low dispersion mode. We report on the results of these observations and interpret our data within the context of other UV spectroscopic studies of magnetic CVs (polars). RX J1802.1+1804 is a relatively bright UV source, with a UV-to-optical flux ratio and emission-line spectrum similar to other well-studied CVs. Our observations insufficiently sample the binary orbit to discern any phase-dependent effects. We found RX J1802.1+1804 to have an unusually large He II λ2733 emission-line strength, and we have also made probable detections of weaker He II lines at 2511, 3203, and possibly 2386Å, in addition to the more commonly detected He II at 1640Å. We suggest that RX J1802.1+1804 is thus anomalous in terms of its overall He II emission-line spectrum among the sample. Several lines of O III λλ3047 and 3133 are apparently detected as well, which is unusual for CVs at the signal-to-noise ratio levels obtainable with IUE long-wavelength spectrograph. Given the seemingly rich spectrum of helium and oxygen emission lines, and the known relationship between He II Lyα and the oxygen lines, i.e., the Bowen fluorescence mechanism, we can, in principle, constrain the size and thermodynamics of the emitting region. This analysis suggests that R~109 cm and ne~1011 cm−3. This physical scale is consistent with the line-emission originating in the accretion column rather than in a hot spot on the white dwarf surface

The INTEGRAL/SPI response and the Crab observations

The Crab region was observed several times by INTEGRAL for calibration purposes. This paper aims at underlining the systematic interactions between (i) observations of this reference source, (ii) in-flight calibration of the instrumental response and (iii) the development and validation of the analysis tools of the SPI spectrometer. It first describes the way the response is produced and how studies of the Crab spectrum lead to improvements and corrections in the initial response. Then, we present the tools which were developed to extract spectra from the SPI observation data and finally a Crab spectrum obtained with one of these methods, to show the agreement with previous experiments. We conclude with the work still ahead to understand residual uncertainties in the response.Comment: 4 pages, 4 figures, Proc. of the 5th INTEGRAL Workshop (Feb. 16-20 2004), to be published by ES

Is Frost Heaving Killing Your Legumes?

Frost heaving is a serious hazard to the maintenance of legume stands on many of our Iowa soils - especially on level claypan soils. But there are some things you can do to reduce your frost heaving losses

Understanding Cheating: From the University Classroom to the Workplace

Cheating is defined as taking information, credit, or reward that one neither deserves nor did the work to achieve. Cheating behavior is often seen as a driver behind many of our current economic problems and the temptation to cheat has been associated with our downward slide in business practice for the past two decades. For example, the current housing crisis has been explained in part as banks cheating in terms of qualifying people for loans. Additionally, current headlines focus on legislators and Wall Street analysts who cheat investors by unfairly taking advantage of inside information not publicly available to others in the market. Cheating defeats fairness of competition and undermines the basis of business integrity. Writers in the business press are expressing concern over the widespread levels of ‘cheating’ among business executives. Enron, HealthSouth, and Tyco, all cheated shareholders in order to pad the pockets of their corporate executives. Some of the smartest and best business minds have fallen subject to the temptation to cheat and the result has been some of the most wideranging financial regulation in our history. The Sarbanes-Oxley and Dodd-Frank Acts were enacted in reaction to the perceived prevalence of cheating by business managers. The controversial new Consumer Financial Protection Bureau is yet another attempt to address this problem. Classroom teachers are also experiencing a growing concern over what seems to be ever increasing levels of cheating among students. Students cheat for a variety of reasons including a felt pressure to maintain good grades and because they perceive many opportunities to cheat but few real penalties for getting caught. Instructor behavior may unwittingly exacerbate the problem by giving unclear or arbitrary assignments that create a climate for cheating when students view the benefits of figuring out and completing the assignment honestly to be minimal at best. The problem of classroom cheating is that students are likely to carry the behaviors they learn in the classroom into the workplace. It is this prospect that leads us to examine the nature of classroom cheating as a precursor to what might happen in actual business settings. It is likely that many of us have cheated at something or in some way, however unimportant, in our lives. We may have taken advantage of unsuspecting others in sports or play and the amount of harm done is probably very little and accepted as part of the interaction. But when the stakes get higher and include academic or business integrity and the validity of a grade or financial statement are at stake, then cheating has significant potential consequences, and needs to be both understood and managed

Yield response of corn in a Planosol soil to subsurface drainage with variable tile spacings

The Edina soil series of southeastern Iowa and northern Missouri are soils of relatively flat topography and poor internal drainage. The need for research data on the feasibility of drainage (both surface and subsurface) on the Edina soils was recognized at the time experiments were begun on the Southern Iowa Experimental Farm, Davis County, Iowa. The yield response of corn to surface drainage by bedding was summarized and reported by Beer et al.3 in 1961. Since initiation of the subsurface drainage experiment in 1949, data on crop-yield response to tile drainage have been collected. The purpose of this bulletin is to present the results of this study as related to the effects of tile drainage on crop yields, with the emphasis on corn, during the period of record. The nature of tile discharge during the growing seasons from 1951 to 1963 also is presented

Super Cracks in Your Fields?

Super cracks are being found in farm fields in a number of Iowa counties following the recent dry seasons. And they\u27re hazardous-to you, your machinery and livestock. Here\u27s what we can tell you about them

Comparison of meadow-kill treatments on a corn-oats-meadow-meadow rotation in northwestern Iowa

An experiment was conducted at the Moody Research Center (formerly Moody Experimental Farm) in northwestern Iowa to examine the effects of meadow-kill on crop yields and on soil moisture in the spring. The experiment utilized a corn-oats-meadow-meadow rotation with meadow-kill treatments applied to the second-year meadow at various times of the growing season. Twenty years (1958-1977) of data were used for the analyses presented in this bulletin. Three treatments were used in the experiment. In the first, the control treatment, the second-year meadow was harvested two or three times. The plots were plowed the following spring before corn was planted. The second treatment was a short fallow” treatment, in which second-year meadow was killed with herbicides in the early fall after the second cutting of hay. The third treatment was a longer fallow treatment, with meadow killed in midsummer after the first hay cutting. Plots receiving the second and third treatments also were spring plowed

XTE J1550-564: INTEGRAL Observations of a Failed Outburst

The well known black-hole X-ray binary transient XTE J1550-564 underwent an outburst during the spring of 2003 which was substantially underluminous in comparison to previous periods of peak activity in that source. In addition, our analysis shows that it apparently remained in the hard spectral state over the duration of that outburst. This is again in sharp contrast to major outbursts of that source in 1998/1999 during which it exhibited an irregular light curve, multiple state changes and collimated outflows. This leads us to classify it as a "failed outburst." We present the results of our study of the spring 2003 event including light curves based on observations from both INTEGRAL and RXTE. In addition, we studied the evolution of the high-energy 3-300 keV continuum spectrum using data obtained with three main instruments on INTEGRAL. These spectra are consistent with typical low-hard-state thermal Comptonization emission. We also consider the 2003 event in the context of a multi-source, multi-event period-peak luminosity diagram in which it is a clear outlyer. We then consider the possibility that the 2003 event was due to a discrete accretion event rather than a limit-cycle instablility. In that context, we apply model fitting to derive the timescale for viscous propagation in the disk, and infer some physical characteristics.Comment: 22 pages, 8 figures, to be published in The Astrophysical Journa

Tree survival and growth on Iowa coal-spoil materials

An evaluation was made of 7- to 8- year survival and growth of 15 tree species of conifers and hardwoods planted on several classes of coal-spoil materials in southeastern Iowa. The more important results were: 1. Green ash survived better than all other species on a variety of coal-spoil materials and appeared best adapted to the more moist sites on the moderately acid to calcareous spoils. 2. Cottonwood grew much faster than all other species on a variety of coal-spoil materials and grew to more than double the height of green ash. 3. Survival and growth of eastern redcedar were best on the calcareous coal-spoil materials. This species is drouth resistant and can be planted on the drier sites. 4. Survival and growth of all pine species tested were very poor on the calcareous coal- spoil materials; apparently, these pines should not be planted on calcareous shales and glacial tills. 5. Of all species tested, jack and Virginia pine appeared best adapted to the dry sites on the strongly and moderately acid spoil materials. Pitch pine was adapted to the same materials but probably should be planted on more moist sites. 6. Red and eastern white pine were best adapted to the slightly acid, more fertile, moist, well-drained sites, and plantings of these species probably should be limited to these locations.https://lib.dr.iastate.edu/specialreports/1036/thumbnail.jp