320 research outputs found
A systematic analysis of Trypanosoma brucei chromatin factors identifies novel protein interaction networks associated with sites of transcription initiation and termination
Measuring protein concentration with entangled photons
Optical interferometry is amongst the most sensitive techniques for precision
measurement. By increasing the light intensity a more precise measurement can
usually be made. However, in some applications the sample is light sensitive.
By using entangled states of light the same precision can be achieved with less
exposure of the sample. This concept has been demonstrated in measurements of
fixed, known optical components. Here we use two-photon entangled states to
measure the concentration of the blood protein bovine serum albumin (BSA) in an
aqueous buffer solution. We use an opto-fluidic device that couples a waveguide
interferometer with a microfluidic channel. These results point the way to
practical applications of quantum metrology to light sensitive samples
Precision Analysis of Evolved Stars
Evolved stars dominate galactic spectra, enrich the galactic medium, expand to change their planetary systems, eject winds of a complex nature, produce spectacular nebulae and illuminate them, and transfer material between binary companions. While doing this, they fill the HR diagram with diagnostic loops that write the story of late stellar evolution. Evolved stars sometimes release unfathomable amounts of energy in neutrinos, light, kinetic flow, and gravitational waves. During these late-life times, stars evolve complexly, with expansion, convection, mixing, pulsation, mass loss. Some processes have virtually no spatial symmetries, and are poorly addressed with low-resolution measurements and analysis. Even a "simple" question as how to model mass loss resists solution. However, new methods offer increasingly diagnostic tools. Astrometry reveals populations and groupings. Pulsations/oscillations support study of stellar interiors. Optical/radio interferometry enable 2-3d imagery of atmospheres and shells. Bright stars with rich molecular spectra and velocity fields are a ripe opportunity for imaging with high spatial and spectral resolution, giving insight into the physics and modeling of later stellar evolution
Precision Analysis of Evolved Stars
Evolved stars dominate galactic spectra, enrich the galactic medium, expand
to change their planetary systems, eject winds of a complex nature, produce
spectacular nebulae and illuminate them, and transfer material between binary
companions. While doing this, they fill the HR diagram with diagnostic loops
that write the story of late stellar evolution. Evolved stars sometimes release
unfathomable amounts of energy in neutrinos, light, kinetic flow, and
gravitational waves. During these late-life times, stars evolve complexly, with
expansion, convection, mixing, pulsation, mass loss. Some processes have
virtually no spatial symmetries, and are poorly addressed with low-resolution
measurements and analysis. Even a "simple" question as how to model mass loss
resists solution. However, new methods offer increasingly diagnostic tools.
Astrometry reveals populations and groupings. Pulsations/oscillations support
study of stellar interiors. Optical/radio interferometry enable 2-3d imagery of
atmospheres and shells. Bright stars with rich molecular spectra and velocity
fields are a ripe opportunity for imaging with high spatial and spectral
resolution, giving insight into the physics and modeling of later stellar
evolution.Comment: Decadal2020 Science White Paper; 6 pages, 12 figure
The Vehicle, 1964, Vol. 6
Vol. 6
Table of Contents
Milepostspage 2
John Fitzgerald Kennedy Memorial Pagepage 4
Sadness No. 4 (Sorgen)Sherry S. Frypage 5
Christian BurialRoger J. Barrypage 7
The World of BeautyDavid Helmpage 9
The Song of the LarksDon Kapraunpage 10
ContrastKeith Haierpage 13
PanoramaDaun Alan Leggpage 13
A Child\u27s View of DeathCherie Brondellpage 14
RegretLiz Puckettpage 16
Brutal WarMary H. Soukuppage 17
aloneLiz Puckettpage 18
MadgeLinda Galeypage 19
Moon WatchingJoel E. Hendrickspage 20
AnalysisLiz Puckettpage 21
UniverseRick Talleypage 21
Anyone Can Be A LuniticRick Towsonpage 22
I, Too, Have A Rendezvous with DeathElaine Lancepage 23
The ReturnRobert D. Thomaspage 24
NamesLarry Gatespage 25
Eternal MomentsDavid Helmpage 25
The Last DaysPauline B. Smithpage 26
BeliefRichard J. Wiesepage 27
StormPauline B. Smithpage 28
ExplosionLiz Puckettpage 29
Autumn EveJoel E. Hendrickspage 29
The Girl On the White PonyLarry Gatespage 31
HoffnungTerry Michael Salempage 33
Stone WallsDaun Alan Leggpage 34
AdorationGail M. Barenfangerpage 37
MirageRoy L. Carlsonpage 38
Nature and NonsenseRick Talleypage 39
A Step Through A Looking GlassMarilyn Henrypage 40
Thoughts of a Summer PastPauline B Smithpage 42
Indiana GrassLarry Gatespage 43
RedondillaRoberta Matthewspage 44
Summer LoveDaun Alan Leggpage 45
To Youth Reaching For MaturityDavid Helmpage 45
Thanksgiving DayJoel E. Hendrickspage 46
Sadness No. 6 (Schatten)Sherry S. Frypage 48https://thekeep.eiu.edu/vehicle/1012/thumbnail.jp
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
- …