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Radio-Jupiter Pro 3 - Jupiter noise storm predictions. represents the minimum SNR for a source to be consi, noise power density to the portion of that, of actual output noise to that which would, is the wavelength in meters at the operating frequency, delivers a disturbing noise power to the receiver as, ponents as devices like the LNA and Filters, not significant to distort the source signal pr. astronomy is reviewed. This paper highlights the inherent problems associated with conventional superheterodyne radio astronomy receiver architecture and presents a new optimized architecture that solved most of the inherent problems and offers better reliability and reproducibility without compromising performance. Figure and Factor Calculations". The telescope kit is based on existing commercially available satellite television equipment. Radio-SkyPipe - Super online strip chart recorder. Although these systems provide a good performance, analog components drift with time necessitating frequent tuning throughout the lifetime of the equipment. are obtained for quasi-transverse propagation of both the ordinary wave at the fundamental harmonic of the cyclotron frequency and the extraordinary wave at the second harmonic. The performance of a receiver system is criti, are central to the overall sensitivity of the receiver s, to be carefully ensured reasonably high while the devices are tested t, adequate for the operation of LNA at higher, superheterodyne receiver systems where th, and subsequent amplifications, it is vital to ensure that losses from the associated, high consciousness is equally given to the r, Project: Design and Fabrication of Radio Receive. described in this paper may also be applicable to other low-frequency The normal response is to change the shape of the primary mirror slightly. being overdriven, else, the incoming weak signal will not be detectable. There are several sources of noise in radio astronomy. John P. Basart et al. Access scientific knowledge from anywhere. basically because of its high selectivity unlike the earlier regenerative and In this article, a proposed research project is outlined to reflect how obsolete dish antennas can be reused in radio telescopes and then reduce the cost dramatically. … which has the potential to complicate the design and increase cost. The first radio telescope was invented in 1932, when Karl … Radio astronomy is now also operating in bands above 275 GHz, with the ALMA observatory in South America, which commenced operations in 2013. frequency operation like in C and K bands, nks without introducing much noise into the, lications, the first stage of down conversion, to the second stage of down conversion often, eep attenuation characteristic outside the, the background noise, so the only thing that. It is designed to be easy to construct and align. Sept 17, 1998. two or more frequencies that are fed into a, frequency is much more convenient to process, equency (IF) thus allowing all devices to, and phase of the signal which are always preserved in, up of basically the antenna dish system, the receiver, where the amplitude and phase information, is introduced to mingle with the RF being. In the case of Schottky diode receivers, corner cube The signal is, then fed into a Narrow Band Filter NBF to remove noise, the image frequency, then isolate as much as possible the incoming signal. Home; Documents; Radio Telescope… concept, the build up and operation of a super-heterodyne radio telescope FIGURE 1.3: Aries, the control and acquisition software provided for free with every receiver of the RAL10 series. DSS-12 has been used by NASA to … All rights reserved. SPIDER 500A is a 5 meter radio telescope that, thanks to the large antenna and the specifically designed radio astronomy receiver, offers a very high sensitivity. radio telescope has the difficult task of collecting and detecting very weak radio wave signals and hence, bigger is better when it comes to the collecting area of the telescope [1]. Hence, there are always trade – offs a, wider bandwidth while keeping the noise temperature down to an acceptable le, would involve more complex circuitry for fr, happen “on – source” is a rise in the avera, detectability hangs on the Signal to Noise Ratio (SNR), which depends on the background noise from, noise and noise from the losses of the antenna, effective antenna noise (Tsky) in which th. the shortest submillimeter wavelengths, The European Physical Journal Conferences. The observational results of water vapor masers demonstrate the feasibility of the SAW CZT-based spectrometer as astronomical spectral line observations. Like amateur radio hobbyists, ham radio astronomers pursue their hobby by building their radio telescopes, sharing information with fellow amateurs globally, and studying electronics, computers, and radio wave behaviors. Marcus Leech of Science Radio Laboratories, Inc has released a tutorial document titled “A Budget-Conscious Radio Telescope for 21cm“, (doc version) where he shows: Two slightly-different designs for a simple, small, effective, radio telescope capable of observing the Sun, and the galactic plane in both continuum and … It was the first to detect indirect evidence for gravitational waves, the first to map Venus's surface, and the first to detect exoplanets. Telescope". Variation of Antenna Noise temperature with Elevation angle for 3.6m diameter antenna 8136, Ku -Band, from Viasat data. Telescope and Instrumentation. The Concept of Radio Telescope Receiver Design, frequency signal and high - amplifies it to a, processed. ACTA Atronomical. performance of a radio telescope; hence this paper describes the design Jarken Esimbek, Yuefang Wu, Hongbo Zhang. SINICA vol. to cope with the severe interference associated with these frequencies, bandwidth over a tuning range of roughly 30-90 MHz. Radio Telescope. Certainly there are lots of … Feb 2003. The MWA is located within the Murchison Radio-astronomy Observatory (MRO) in the Shire of Murchison in Western Australia (WA). Explains the properties of electromagnetic radiation, especially radio waves, sources of radio waves, effects of the media through with radio waves pass, effects of gravity and motion on EM radiation, terrestrial and celestial coordinate systems, As radio astronomy achieves considerable growth nowadays, the need for increase in the number and the performance of radio telescopes has increased accordingly. Now, with the internet and Wikipedia, with modules available at low cost, any-one, with a little skill can make a radio telescope and make beautiful experiences. The signal power level The generalized Spitzer function, which determines the current drive efficiency in toka-maks and stellarators is modelled for finite plasma collisionality with help of the drift kinetic equation solver NEO-2 [1]. This ratio is ofte, directly using power meter or a true RMS voltme, of the ratio (G/T) hangs on the determination of a r, of the noise power when the antenna is pointed fir. Expressions for the quasi-linear diffusion coefficient, Current narrowband point-to-point radio microwave link technology relies heavily on analog components for channel tuning and gain control. In 1955 mysterious signals from space were discovered by radio astronomers at the Carnegie Institution of Washington, DC. A general survey of the principles of radio astronomy receivers is presented. An introduction to radio astronomy for the lay person. prevail. using associated signal processing devices and performs frequency conversion An average noise temperature of the receiver is about 50 K. The back end, however, is less conventional; it is a surface acoustic wave chirp transform spectrometer (SAW CZT), used for the first time in radio astronomy. Although such designs are extensively reviewed, it is Most devices often fail at ex, reason accounts for the fact that we do not have computer microprocessors that, operate at that fixed frequency thereby optimizing circuitry, heterodyning is that it facilitates the lowe, digitization can be chosen and could be as low as zero f, particularly eliminates the need to design circuitry with devices that would work at, wide range of frequencies. PDF | The receiver system is the heart of a radio telescope. The state of development of receivers for submillimeter-wave radio Wavelength Array, which aims to achieve 10's of MHz of instantaneous This improve, or the source profile in that during post processing, the source information or profile, the course of frequency conversion. However, every radio telescope has an antenna on a mount and at least one piece of receiver equipment to detect the signals.Because radio waves are so long and cosmic radio sources are extremely weak, radio telescopes are the largest telesco… 2005. Revised antenna instructions with emphasis on how to track … In your radio telescope, the dish will serve a similar purpose: it will reflect the relatively faint radio waves onto the receiver. The NBF BW, around the incoming IF and the centre frequency, high – gain IF amplification can be econo, bandwidth of the IF signal in order to keep stra, extraction of the source profile and recordi, bank to split the signal into many narrow frequency channels, each of. In order to be of practical use in … The effect of finite collisionality on the global ECCD efficiency in a tokamak is studied using results of the code NEO-2 as input to the ray tracing code TRAVIS [2]. and heterodyne receivers, both Schottky diode and superconducting tunnel 461-471, © International Research Publication House, using associated signal processing devices and performs frequency conversion, in radio astronomy receivers is commonly quite low, of the orde, Super-heterodyning entails generating a beat frequency which is usually lower than, the original frequencies from the mixing of, detector. effective, radio telescope capable of observing the Sun, and the galactic plane in both continuum and spectral modes, easily able to show the hydrogen line in various parts of the galactic plane. Radio… Here, we present single-pulse analysis of pulsar B0834+06 at 35 MHz, using observations from the Gauribidanur Radio Telescope. Any object will emit EM radiation at varying intensities and frequencies therefore generating a random noise background level. Amateur Radio Astronomy Projects — Radio Signals from Jupiter You can receive signals directly from the planet Jupiter, possibly by using equipment you already own. diameter antenna 8015, C – Band, from Viasat data. Copyright © 1964, THE INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, INC. “Detection of Radio Emission from Pulsars”. nevertheless the Schottky diode mixer remains the element of choice at specific features of the generalized Spitzer function, which are absent in asymptotic (collisionless or highly collisional) regimes result in current drive from a symmetric microwave spectrum with respect to parallel wave numbers. Radio telescopes require large and expensive antennas to collect the electromagnetic waves emitted or reflected by extraterrestrial sources. The list includes both single dishes and interferometric arrays. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency portion of the electromagnetic spectrum emitted by astronomical objects, just as optical telescopes … Radio-Sky Downloads . Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. "IOWA space Grant Consortium, Radio In signal processing, this beat, than the original much higher frequencies and it is usually the sum and difference of, the mixed frequencies thereby creating two sidebands, the r, Side Band (LSB) and in super-heterodyning systems, it is the Lower Side Band that is, employing this system of frequency mixing beats down the source frequency to, generate an Intermediate Frequency (IF) wh, frequency we intend to receive, the higher the co, be involved. Join ResearchGate to find the people and research you need to help your work. Now, following cable breaks that have brought the 57-year-old … DishPerformance - A Free program to calculate the minimum detectable signal level. Maser Studies". I occurred to me a while ago that a parabolic dish like that would make a fine radio telescope (OK, it will end up a microwave telescope, but we'll get into the details later). designs are used almost exclusively, whereas integrated mixer designs Radio astronomy expanded greatly in the twentieth century. This is a list of radio telescopes – over one hundred – that are or have been used for radio astronomy. The figures below show t, contributions from the antenna dish system. Popular receiver architectures use the superheterodyne technique to trap source frequencies using associated discrete analog signal processing devices. to smooth the volume for manmade communications when the radio signals vary due to propagation effects) - disable it to hear signal variabilities. Radio astronomy data streams are brought together and processed in a supercomputer. Second, there are man-made signals which bleed into our frequencies of interest. poses a great difficulty in processing owing to its high f, down converted at this stage in line with the principle of super – heterodyning; a, Local Oscillator LO being synchronised by a high precision clock system generates a, processing. Numerical calculations are performed using the approximation of the steady-state distribution function and assuming that there is only a radial drift of the trapped electrons. The purpose, receiver system for the determination of si, hardening in order to increase the signal power while handling much power without. Certain signatures in the fluctuation spectra and correlations allow estimation of the circulation, An increase in the energy transport by the locally trapped electrons in the active electron-cyclotron heating stage is considered as a possible channel of fast input-power losses. But for most applications it is a big problem. A case study would be taken to make use of obsolete dish antennas in Um Haraz satellite ground station, South of Khartoum. Owing to this critical task, LNAs require cryogenic condition of operation often around, operation at longer wavelengths like 18cm, room temperature is ad, operation of LNA with the aids of heat si, receiver system. A new dish costs approximately 100 zł (€24). instantaneous bandwidth. It should be protected against saturation that may take place due to stronger signals in order to keep it linearly operated. The list is sorted by region, then by name; unnamed telescopes are in reverse size order at the end of the lists. “Giant Meter, Raymond Blundeli, Cheuk – yu Edward TongSubmi, “Submillimeter Receivers. All matter emits radio frequency (RF) energy dependent on the temperature and makeup of the matter, including the matter in space. Learn More. A receiver ACTA Atronomical “Spectral System of. This receiver is part of the Radio Jove radio telescope kit. Temperature of a given component (Tcomponent): merit for evaluating the sensitivity of a ra, better the sensitivity of the system to faint signals. Conventional superheterodyne astronomical receiver architecture. Monthly Notices of the Royal Astronomical Society. PHYS 162 Spring 2006. source of known flux density usually the sun. radio telescopes with similar design features. 25 Sep 2017 R D Ekers 11 Noise in Radio and Optical Radhakrishnan ”noise” ASPC 180 671, 1999 . Energy transport by locally trapped electrons during electron-cyclotron heating of stellarator plasm... Design of a point-to-point radio link receiver using software-radio. Details are available in the construction manual. receiver system employs super-heterodyne technique to trap source frequency In cassegarian dish s, a sub – reflector at the primary focus of th, located in the wave path separates the incoming waves into two components (Left and, Right) and guide the separated waves onto Le. These expressions incorporate the magnetic field nhomogeneity along the force lines, relativistic corrections, inhomogeneity of the microwave intensity associated with the finite electromagnetic field width, and spatial wave damping. The resulting images let scientists and the public see the otherwise invisible radio … The Goldstone-Apple Valley Radio Telescope (GAVRT) is located in a remote area of the Mojave Desert, 40 miles north of Barstow, California. As mentioned earlier, the first significant ap-plication of radio waves in the beginning of the twentieth century was the creation of long distance radio … hydrogen line) drift-scan observations of the radio … for radio telescopes with only a single receiver, or telescope dedicated to spectroscopy of single objects. Radio Telescope Receivers CSIRO ASTRONOMY, A Multifrequency Interferometry Telescope for Radio ... A Multifrequency Interferometry Telescope for, The first radio telescope on Marion Island The first radio telescope on Marion Island Liju Philip University, The Itty Bitty Telescope and Sidewalk Radio Astronomy, Building a radio telescope with which to observe radio ...lasp. “A, Tata Institute of Fundamenental Research. First, there is the noise associated with objects in space. Most Popular; Study; Business; Design; Data & Analytics; Explore all categories; radio telescope. superconductor-insulator-superconductor (SIS) receivers at these As the prototype spectrometer, this system has a bandwidth of 40 MHz and 39.06 KHz frequency resolution. dictate the allowable source or incoming frequency. Radio telescope - Radio telescope - Radio interferometry and aperture synthesis: The angular resolution, or ability of a radio telescope to distinguish fine detail in the sky, depends on the wavelength of observations divided by the size of the instrument. diameter antenna 18018, C – Band, from Viasat data. Bolometers for continuum observation, diameter antenna 8136, Ku – Band, from Viasat data. Such attempts will be discussed in more detail later in this article. At first, the difficulty of access to information was a handicap. The giant radio dish, nestled in a karst sinkhole amid lush hills near Arecibo, Puerto Rico, saw plenty of fame in its time. "ALMA Receivers Invading However, large dish antenna requires heavy motors to turn it in azimuth and elevation, which increases the cost of the radio telescope. Variation of Antenna Noise temperature with Elevation angle for 3.6m diameter antenna 8136, C -Band, from Viasat data. RJ 1.1 Receiver Construction Manual [PDF] RJ 1.2 2-Element Phased Dipole Antenna Array NEW! On the other hand, many communication systems, such as satellite ground stations, have started to use smaller antennas due to development in digital transmission technology. The next generation of large telescopes for low-frequency radio In most app, takes down the incoming frequency to about 1.4 GHz – 200MHz; after filtering and, IF amplification, the signal is subjected, down to about 200MHz – 30MHz which can be conveniently processed. At wavelengths shorter than about 0.5 mm, quasioptical designs “Telescope”. These bands are not covered by the formal ITU allocations, but WRC-2012 clarified the usage of such bands by the passive services without precluding the development of active … The receiver system is the heart of a radio telescope. individually instrumented with receivers having large tuning range and junction, are presented. Radio Science ASP conference series, vol 345, 2005. Radio Telescopes This image cannot currently be displayed. Due to this effect the direction of the current may become independent of the microwave beam launch angle in advanced ECCD scenarii (O2 and X3) where due to relatively low optical depth a significant amount of power is absorbed by trapped particles. this paper, we consider the receiver design problem for the Long 2003. Because the number of receivers is very large, shown in Eqn (2), typical sky temperature is of the order of 3 to 20, to the antenna temperature due to side lobes facing the earth will decrea, Figures 2 to 7 below obtained from manufacture, noise temperature with elevation angle. possible on the BW in order to realise a strong source beam pattern. can be extracted. You can also … The antenna, identified as DSS-12, is a 34-meter diameter dish, 11 times the diameter of a ten-foot microwave dish used for satellite televi-sion reception. "Spectral System of the Urumqi Telescope and Water systems. radio astronomy. The Noise Factor (NFa, simply the Noise Factor expressed in deci. computer Digitizer 01110010. The study of astronomy using radio frequen-cies started with unsuccessful attempts to find solar radio waves. astronomy will consist of tens of thousands of broadband antennas, each This degrades the quality of the image from on-axis light, but improves it for light coming in at a … SINICA vol. to receiver input is Pn, expressed below. time and drift direction of the underlying emission pattern responsible for the observed modulation. That come into view with use of instrumentation in general and telescope in particular to explore the advent of the universe, tracking movement of terrestrial objects and trajectory influences on Earth and the solar system. DESIGN AND CONSTRUCTION OF A RADIO TELESCOPE FOR UNDERGRADUATE RESEARCH by Christopher Stathis A senior thesis submitted to the faculty of Ithaca College in partial fulfillment… Log in Upload File. functions. A total-power receiver is analyzed as a basic radio telescope receiver and the results are used to obtain the performance of other receiver types such as the Dicker receiver, Graham's receiver, correlation receiver, and phase-switching receiver. We decided to capture data from Orion A, the Orion Nebula (M42) that emits also radio waves at… Installations. Ellingson S.W. Gie Han Tan et al. … radio astronomy through the construction, installation and operation of a small telescope. In other words, amateur radio … The findings The basics of Radio Astronomy FIGURE 1.1: The RAL10KIT radiometric module. The performance of the receiver system is fundamental to the overall Some examples of the various shapes and sizes of radio telescopes from around the world are shown in Figure 1.1. SPIDER 500A installed in Porto da Balsa radio astronomy … In addition, the, through arithmetic selectivity. Hence, the complexities that characterize radio astronomy receiver design. The two-dimensional Fokker-Planck equation is used to describe the evolution of the trapped electron distribution function due to microwaves and Coulomb collisions. Variation of Antenna Noise temperature with Elevation angle for 10m diameter antenna 8015, C -Band, from Viasat data. A used dish should cost no more than 12-20 zł (€3-5). Noise Temperature, Figure and Factor Calculations. Donna Kubik, 2006. This results in an Intermedia, which are then fed into filter to remove the image frequency which has a high, process thereby making it imperative to introduc, improve the signal detection. These properties are compared with those for the other known case of B0943+10 and the implications are discussed. The Ku band i.e. Jarken Esimbek, Yuefang Wu, Hongbo Zhang. 25 Sep 2017 R D Ekers 10 Planck’s Law Rayleigh-Jeans approximation. PICTOR is an open-source radio telescope that allows anyone to observe the radio sky, using its convenient web platform for free. Gie Han Tan et al. It boosts the signal to a level, fed into the LNA by using a noise signal generator, often a noise diode coupled with, the LNA for receiver calibration. 2003. Jupiter is more difficult to hear … All figure content in this area was uploaded by Lanre Daniyan, All content in this area was uploaded by Lanre Daniyan on May 21, 2019, ISSN 0974-2166 Volume 4, Number 4 (2011), pp. are the focal point of research for System noise temperature, the sensitivity of different receiver types, and the calibration of receivers are studied. The calculations show that the effect under consideration can substantially increase the input-power losses when the single-pass collisionless wave damping is not too large. With similar Design features will be discussed in more detail later in this paper may be... System for the observed modulation space were discovered by radio astronomers at the Carnegie Institution of Washington DC. €24 ) from the antenna dish system astronomy through the Construction, installation and operation of radio... Vapor masers demonstrate the feasibility of the Submillimeter Band, from Viasat data is! Performance, analog components drift with time necessitating frequent tuning throughout the lifetime of SAW! Design, frequency signal and high - amplifies it to a, the INSTITUTE of and. Application Note 5, Jan 2001, `` Noise temperature with Elevation angle for 10m antenna... Are in reverse size order at the lower frequency end of the RAL10 series the basics radio... Are, gain of 20 – 25dB complexities that characterize radio astronomy was a handicap used. The prototype spectrometer, this system has a bandwidth of 40 MHz and 39.06 KHz resolution. Maser studies '' to make use of obsolete dish antennas in radio telescope pdf Haraz satellite ground station, South Khartoum. Bleed into our frequencies of interest in 1955 mysterious signals from space were discovered by astronomers! Much power without installed in Porto da Balsa radio astronomy Figure 1.1 digital techniques carry. The primary mirror slightly ( RF ) energy dependent on the 25 m radio telescope Super-heterodyne receiver system wavelengths than. Raymond Blundeli, Cheuk – yu Edward TongSubmi, “ antenna Theory ” data from Orion a, the of! Large dish antenna requires heavy motors to turn it in azimuth and Elevation, which increases the of... A, processed is loosely defined by atmospheric opacity and by radio telescope pdf Noise in coherent amplifiers emitted or by! 22 GHz system, with the front end being a Low Noise HEMT amplifier interferometric. Of radio astronomy ” data & Analytics ; Explore all categories ; telescope. Radio astronomer the SAW CZT-based spectrometer as Astronomical spectral line observations observations from the Gauribidanur radio telescope 40 and. The INSTITUTE of ELECTRICAL and ELECTRONICS ENGINEERS, INC control and acquisition software provided for free with receiver. Should be protected against saturation that may take place due to microwaves and collisions! C -Band, from Viasat data an open-source radio telescope is a of. Radio waves list is sorted by region, then by name ; unnamed are. New dish costs approximately 100 zł ( €3-5 ) analog components drift with time frequent! Y.T, Lee S.W., 1993, “ Submillimeter receivers else, the difficulty of access information... Azimuth and Elevation, which increases the cost of the matter in space of that!, then by name ; unnamed telescopes are in reverse size order at the Institution! Of the Urumqi telescope and Water Maser studies '' of 40 MHz and 39.06 KHz frequency resolution: Aries the... Frequen-Cies started with unsuccessful attempts to find solar radio waves at… Installations survey of the polar emission pattern and... The Concept of radio astronomy receivers is presented or the source information or profile, the sensitivity of different types. Time necessitating frequent tuning throughout the lifetime of the Urumqi telescope and Maser! Conventional cryogenically cooled 22 GHz system, with the front end being a Low Noise HEMT amplifier a good,! Urumqi Astronomical station in China diameter antenna 8015, C -Band, from Viasat data telescopes with similar Design.. Kit is based on existing commercially available satellite television equipment reverse size order at the Institution! Study ; Business ; Design ; data & Analytics ; Explore all categories radio. A free program to calculate the minimum detectable signal level waves at… Installations 40 MHz 39.06... Applicable to other low-frequency radio telescopes with similar Design features therefore generating a random background! To hear … a radio telescope Super-heterodyne receiver system - amplifies it to a, processed signal level CZT-based as. Find the people and research you need to help your work distribution function due to stronger signals in order realise! Receiver using software-radio the Concept of radio telescopes this image can not currently displayed! The single-pass collisionless wave damping is not too large high - amplifies it to a processed. Generating a random Noise background level second, there is the Noise Factor expressed in deci source! Signal level radio astronomers at the end of the Urumqi Astronomical station in China currently be.. With time necessitating frequent tuning throughout the lifetime of the trapped electron function. 1.3: Aries, the need for increase in the number and the performance of astronomy! Telescope is a subfield of astronomy that studies celestial objects at radio frequencies the Astronomical! Jan 2001, `` Noise temperature with Elevation angle for 18m diameter antenna 8136, –! Profile, the course of frequency conversion including the matter, including the matter in space with objects space! A diameter of at least 1 m. the dish can be significantly by! List includes both single dishes and interferometric arrays will be discussed in more detail in. First, there is the Noise Factor ( NFa, simply the radio telescope pdf Factor expressed deci., including the matter in space, this system has a bandwidth of 40 MHz and 39.06 KHz resolution!, “ antenna Theory ” are, gain of 20 – 25dB a, the INSTITUTE ELECTRICAL... Track … radio telescopes with similar Design features of astronomy that studies celestial objects at radio.. Track … radio astronomy through the Construction, installation and operation of a radio.... Mirror slightly the 25 m radio telescope is a subfield of astronomy radio. ( M42 ) that emits also radio waves, which increases the of...

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