Searching for chameleon-like scalar fields with the ammonia method. II. Mapping of cold molecular cores in NH3 and HC3N lines

Abstract

(Abridged) In our previous work we found a statistically significant offset Delta V = 27 m/s between the radial velocities of the HC3N(2-1) and NH3(1,1) transitions observed in molecular cores from the Milky Way. This may indicate that the electron-to-proton mass ratio, mu = m_e/m_p, increases by 3x10^{-8} when measured under interstellar conditions with matter densities of more than 10 orders of magnitude lower as compared with laboratory (terrestrial) environments. We now map four molecular cores L1498, L1512, L1517, and L1400K selected from our previous sample in order to estimate systematic effects in Delta V due to possible velocity gradients. We find that in two cores L1498 and L1512 the NH3(1,1) and HC3N(2-1) transitions closely trace the same material and show an offset of Delta V = 26.9 +/- 1.2_stat +/- 3.0_sys m/s throughout the entire clouds. The measured velocity offset, being expressed in terms of Delta mu = (mu_obs - mu_lab)/mu_lab, gives Delta mu = (26 +/- 1_stat +/- 3_sys)x10^{-9}.

14 pages, 5 figures, 6 tables. Accepted for publication in Astronomy and Astrophysics

References in corpus (10)

• Environmental Dependence of Masses and Coupling Constants
• On the internal structure of starless cores. II. A molecular survey of L1498 and L1517B
• Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe
• Enhanced sensitivity to time-variation of m_p/m_e in the inversion spectrum of ammonia
• On the frequency of N2H+ and N2D+
• Ultracold molecules: new probes on the variation of fundamental constants
• Detecting Chameleons: The Astronomical Polarization Produced by Chameleon-like Scalar Fields
• The Effect of a Chameleon Scalar Field on the Cosmic Microwave Background
• Submillimeter water and ammonia absorption by the peculiar z~0.89 interstellar medium in the gravitational lens of the PKS 1830-211 system
• Stringent bounds to spatial variations of the electron-to-proton mass ratio in the Milky Way

Cited by in corpus (36)

• Modified Gravity and Cosmology
• Search for New Physics with Atoms and Molecules
• Varying constants, Gravitation and Cosmology
• Robust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes
• A search for varying fundamental constants using Hz-level frequency measurements of cold CH molecules
• Methanol as a tracer of fundamental constants
• The Constancy of the Constants of Nature: Updates
• An upper limit to the variation in the fundamental constants at redshift z = 5.2
• Evidence for speed-dependent effects in NH3 self-broadened spectra: towards a new determination of the Boltzmann constant
• Chameleons in the Early Universe: Kicks, Rebounds, and Particle Production
• QSO 0347-383 and the invariance of m_p/m_e in the course of cosmic time
• New bounds on macroscopic scalar-field topological defects from non-transient signatures due to environmental dependence and spatial variations of the fundamental constants
• Limits on the spatial variations of the electron-to-proton mass ratio in the Galactic plane
• Fundamental constants and high resolution spectroscopy
• Practical Limitations on Astrophysical Observations of Methanol to Investigate Variations in the Proton-to-Electron Mass Ratio
• Testing the variability of the proton-to-electron mass ratio from observations of methanol in the dark cloud core L1498
• Search for variation of fundamental constants: Strong enhancements in $X^2\Pi$ cations of dihalogens and hydrogen halides
• Accurate Prediction of the Ammonia Probes of a Variable Proton-to-Electron Mass Ratio
• Varying alpha from N-body Simulations
• Distinguishing modified gravity models
• Constraining cosmologies with fundamental constants I. Quintessence and K-Essence
• Testing the weak equivalence principle by differential measurements of fundamental constants in the Magellanic Clouds
• Runaway Domain Wall and Space-time Varying alpha
• Chameleon Induced Atomic Afterglow
• An Environmental Variation of Constants
• Enhanced sensitivity to a possible variation of the proton-to-electron mass ratio in ammonia
• Sensitivity to alpha-variation in ultracold atomic-scattering experiments
• Sensitivity of the isotopologues of hydronium to variation of the electron-to-proton mass ratio
• Laser spectroscopy of cold molecules
• Sensitivity of microwave transition in H2O2 to variation of the electron-to-proton mass ratio
• Probing the electron-to-proton mass ratio gradient in the Milky Way with class I methanol masers
• Hyperfine-resolved rotation-vibration line list of ammonia (NH${}_3$)
• Cyanopolyyne line survey towards high-mass star-forming regions with TMRT
• Searching for cosmological variation of the proton-to-electron mass ratio using a single $H_2$ system
• Anomalous phosphine sensitivity coefficients as probes for a possible variation of the proton-to-electron mass ratio
• Space-time variation of the electron-to-proton mass ratio in a Weyl model