67 research outputs found
Space fusion energy conversion using a field reversed configuration reactor: A new technical approach for space propulsion and power
The fusion energy conversion design approach, the Field Reversed Configuration (FRC) - when burning deuterium and helium-3, offers a new method and concept for space transportation with high energy demanding programs, like the Manned Mars Mission and planetary science outpost missions require. FRC's will increase safety, reduce costs, and enable new missions by providing a high specific power propulsion system from a high performance fusion engine system that can be optimally designed. By using spacecraft powered by FRC's the space program can fulfill High Energy Space Missions (HESM) in a manner not otherwise possible. FRC's can potentially enable the attainment of high payload mass fractions while doing so within shorter flight times
NASA-NIAC 2001 Phase I Research Grant on Aneutronic Fusion Spacecraft Architecture
This study was developed because the recognized need of defining of a new spacecraft architecture suitable for aneutronic fusion and featuring game-changing space travel capabilities. The core of this architecture is the definition of a new kind of fusion-based space propulsion system. This research is not about exploring a new fusion energy concept, it actually assumes the availability of an aneutronic fusion energy reactor. The focus is on providing the best (most efficient) utilization of fusion energy for propulsion purposes. The rationale is that without a proper architecture design even the utilization of a fusion reactor as a prime energy source for spacecraft propulsion is not going to provide the required performances for achieving a substantial change of current space travel capabilities
Spacecraft Applications for Aneutronic Fusion and Direct Energy Conversion
No abstract availabl
Discovery of Two Distant Type Ia Supernovae in the Hubble Deep Field North with the Advanced Camera for Surveys
We present observations of the first two supernovae discovered with the
recently installed Advanced Camera for Surveys (ACS) on the Hubble Space
Telescope. The supernovae were found in Wide Field Camera images of the Hubble
Deep Field North taken with the F775W, F850LP, and G800L optical elements as
part of the ACS guaranteed time observation program. Spectra extracted from the
ACS G800L grism exposures confirm that the objects are Type Ia supernovae (SNe
Ia) at redshifts z=0.47 and z=0.95. Follow-up HST observations have been
conducted with ACS in F775W and F850LP and with NICMOS in the near-infrared
F110W bandpass, yielding a total of 9 flux measurements in the 3 bandpasses
over a period of 50 days in the observed frame. We discuss many of the
important issues in doing accurate photometry with the ACS. We analyze the
multi-band light curves using two different fitting methods to calibrate the
supernovae luminosities and place them on the SNe Ia Hubble diagram. The
resulting distances are consistent with the redshift-distance relation of the
accelerating universe model, although evolving intergalactic grey dust remains
as a less likely possibility. The relative ease with which these SNe Ia were
found, confirmed, and monitored demonstrates the potential ACS holds for
revolutionizing the field of high-redshift SNe Ia, and therefore of testing the
accelerating universe cosmology and constraining the "epoch of deceleration".Comment: 11 pages, 8 embedded figures. Accepted for publication in Ap
The Mid-Infrared Environments of High-Redshift Radio Galaxies
Taking advantage of the impressive sensitivity of Spitzer to detect massive
galaxies at high redshift, we study the mid-infrared environments of powerful,
high-redshift radio galaxies at 1.2<z<3. Galaxy cluster member candidates were
isolated using a single Spitzer/IRAC mid-infrared color criterion,
[3.6]-[4.5]>-0.1 (AB), in the fields of 48 radio galaxies at 1.2<z<3. This
simple IRAC color selection is effective at identifying galaxies at z>1.2.
Using a counts-in-cell analysis, we identify a field as overdense when 15 or
more red IRAC sources are found within 1arcmin (i.e.,~0.5Mpc at 1.2<z<3) of the
radio galaxy to the 5sigma flux density limits of our IRAC data (f3.6=11.0uJy,
f4.5=13.4uJy). We find that radio galaxies lie preferentially in medium to
dense regions, with 73% of the targeted fields denser than average. Our
(shallow) 120s data permit the rediscovery of previously known clusters and
protoclusters associated with radio galaxies as well as the discovery of new
promising galaxy cluster candidates at z>1.2.Comment: 14 pages, 7 figures, 3 tables, accepted for publication in Ap
The Spiderweb galaxy: a forming massive cluster galaxy at z~2
We present a deep image of the radio galaxy MRC 1138-262 taken with the
Hubble Space Telescope (HST) at a redshift of z = 2.2. The galaxy is known to
have properties of a cD galaxy progenitor and be surrounded by a 3 Mpc-sized
structure, identified with a protocluster. The morphology shown on the new deep
HST/ACS image is reminiscent of a spider's web. More than 10 individual clumpy
features are observed, apparently star-forming satellite galaxies in the
process of merging with the progenitor of a dominant cluster galaxy 11 Gyr ago.
There is an extended emission component, implying that star formation was
occurring over a 50 times 40 kpc region at a rate of more than 100 M_sun/yr. A
striking feature of the newly named ``Spiderweb galaxy'' is the presence of
several faint linear galaxies within the merging structure. The dense
environments and fast galaxy motions at the centres of protoclusters may
stimulate the formation of these structures, which dominate the faint resolved
galaxy populations in the Hubble Ultra Deep Field. The new image provides a
unique testbed for simulations of forming dominant cluster galaxies.Comment: 5 pages, 2 figures (reduced to grayscale); ApJ Letter
Understory 2014
âArt is the struggle to be, in a particular sort
of way, virtuous.â âIris Murdoch
Indeed, when we embark on any creative adventure
it is with the purpose of conveying a certain truth; an
emotion, an idea that brings us together and reminds us
of the innate consciousness that dwells within.
Understory is emblematic of this; where individuals
intent on honing their craft can join others to become a
part of something greater, their work immortalized to
become a time capsule. Decades from now a volume of
Understory may be discovered on a dusty bookshelf in
some forgotten corner and the lucky explorer who finds it
shall be enlightened by pages of gold.
We, as editors of Understory 2014, have worked
very hard this year to put together a journal that showcases
the very best of the University of Alaska Anchorage
undergraduate student work. We hope you enjoy your
journey through this issue as much as we have enjoyed ours.
Thank you to the English and Art Departments,
for the staff and facultyâs unerring support of our club;
to Provost Baker, for seeing and believing in the vision
of Understory; and to our clubâs faculty advisor, Douglass
Bourne, for his guidance and tireless assistance. Finally,
thank you to the wonderful students who submit such
excellent work each year. Without your passion for the
arts, we would not be here.Staff / Letter from the Editors / Glass Blower / Writing / Obsolete Evolution / Permafrost / Phoenix / Untitled / Ratio / Tripping / Abiogenesis / My Heart Beats for You / Meeting of the Fingerprint Lines / You Are No Stranger / Nightmare Fuel / Cane-Sugar / Gossamer Strands / Panthera Gold / Butterfly / A Mantis Too Far / Long and Winding Road / Chasing Shadows / Merisunas / Chequer Grove / Modzilla / Beans / Little Red and Mr. Wolf / In Memoriam, Joel Fletcher Armstrong / Glance / Courage / Uranium Waltz / Danger / Journey to the West / Antumbra / Roaring Like a Lion / Pre-boarding / Untitled / How Do You Say a Word / Fishing for Doom/ Contributor
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Inventory Data Package for Hanford Assessments
This document presents the basis for a compilation of inventory for radioactive contaminants of interest by year for all potentially impactive waste sites on the Hanford Site for which inventory data exist in records or could be reasonably estimated. This document also includes discussions of the historical, current, and reasonably foreseeable (1944 to 2070) future radioactive waste and waste sites; the inventories of radionuclides that may have a potential for environmental impacts; a description of the method(s) for estimating inventories where records are inadequate; a description of the screening method(s) used to select those sites and contaminants that might make a substantial contribution to impacts; a listing of the remedial actions and their completion dates for waste sites; and tables showing the best estimate inventories available for Hanford assessments
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