OPINION
BOLGER, Judge.Harrietta Ulak pleaded guilty to assault in the third degree for injuring C.S. on more than one occasion, and Ulak admitted the aggravating factors that C.S. was a particularly vulnerable victim, and that her conduct manifested deliberate cruelty. At her sentencing hearing, however, Ulak denied that she had ever injured C.S. deliberately, and she requested that the superior court excise from the presentence report her grandechil-dren's hearsay statements that she had deliberately abused C.S. on numerous occasions. We remand the case and direct the superior court to determine the factual basis for Ulak's plea. If the grandchildren's statements comprise the factual basis for Ulak's plea and the aggravating factors she admitted, these statements may remain in the presentence report.
Background
C.S. was a three-year-old child that Ulak and her husband took into their home approximately nine months before this case arose. The State indicted Ulak on four counts of assault for repeatedly beating C.S. Ulak entered into a plea agreement in which she agreed to plead guilty to one count of assault in the third degree for "recklessly caus[ing] physical injury to a child under 10 years of age on more than one occasion." 1 Ulak also agreed to admit two aggravating factors: that her conduct during the commission of the offense manifested deliberate eru-elty to C.S., and that she knew or reasonably should have known that C.S. was particularly vulnerable due to her extreme youth.2
Prior to the sentencing hearing, Ulak objected to several hearsay assertions made by her grandchildren that were included in the presentence report. In response, the State argued that Ulak was not entitled to deletion of these statements because the statements formed the factual basis for her guilty plea.
All of the disputed statements concerned Ulak's infliction of physical injury upon C.S. Ulak disputed the statements of her granddaughter, Kenny: that Ulak tried to kill C.S., punched C.S. hard enough to give her two *1256black eyes and a broken nose, pulled her hair, put a knife to her throat, and poked her in the stomach with a knife. Ulak also disputed the statements of her granddaughter, Mary Jane: that Ulak hit C.S. with a closed fist, kicked her, and frightened her with a knife. All of these statements arguably underlie the charge that Ulak admitted: that she recklessly caused physical injury to C.S. on more than one occasion.
The presentence report also contained additional evidence related to Ulak's offense. For example, when two social workers came to Ulak's house, they found that C.S. was moving very slowly and appeared to be in pain. Her face was completely swollen with dark purple bruises, and she had bruises on her neck and arms, dried blood on her nose and mouth, bald spots on her head, sores all over her head, and a cut across the back of her head. Her hair was singed on both sides of her head. But the social workers did not witness any of the abuse that had caused these injuries.
At the sentencing hearing, Ulak testified and denied the hearsay reports by her grandchildren. Ulak said that she spanked C.S. to discipline her, but that she never hit C.S. with a closed fist. Ulak denied that she ever hit C.S. deliberately for her personal satisfaction.
Ulak also called her husband, Paul Ulak, as a witness on her behalf. He described his wife as "a good mother." He testified that he had seen Ulak hit C.S., but denied that Ulak had ever used excessive force.
Superior Court Judge Marvin Hamilton denied Ulak's motion to strike her grandchildren's statements from the presentence report. Instead, he supplemented the record with Ulak's affidavit setting forth her competing version of events. Judge Hamilton imposed a sentence of 4 years with 1 year suspended, and Ulak now appeals.
Discussion
Upon a defendant's objection, a sentencing judge is required to determine the admissibility of assertions contained in the presentence reports.3 Ordinarily, verified assertions of prior misconduct are admissible for sentencing.4 But when the defendant denies hearsay assertions regarding prior misconduct under oath, the State is required to prove that the declarants are unavailable or to present live testimony to support their assertions.5 The sentencing judge then decides whether the assertions are true. If the assertions are not proven, then the judge must delete the assertions from the presen-tence report.6
Special rules apply to assertions that relate to the charge under consideration at the sentencing hearing. A plea of guilty or no contest constitutes an admission that establishes the truth of the charge for sentencing purposes.7 The factual assertions that underlie the offense are considered to be true even though the defendant might deny those assertions under oath. Therefore, even when the defendant testifies that he is innocent, the assertions underlying the offense should not be stricken from the presentence report.8
The same rule applies to the facts that underlie any conceded aggravating factors. The prosecution is required to give notice of the factual basis for each factor that it alleges.9 The sentencing judge is required to enter specific findings on aggravating fac*1257tors as part of the sentencing process.10 The defendant may waive his right to a trial or hearing by admitting these factors.11 But even when the defendant admits an aggravating factor, the judge has a duty to ensure that there is a reasonable basis for the admission.12 Accordingly, when the defendant makes such an admission, the facts that support the aggravating factor are deemed to be true for sentencing purposes.
We have not previously resolved the process that a judge should use to determine whether assertions in the presentence report underlie the offense to which the defendant has pleaded guilty or no contest, and therefore must remain in the report even if the defendant objects to the assertions. However, the answer is already provided in Alaska Criminal Rule 11) for defendants like Ulak, who enter a plea of guilty.
Rule 11) requires that "The court shall not enter a judgment upon a plea of guilty without first being satisfied that there is a reasonable basis for the plea." The court is required to explicitly determine that a guilty plea is supported by an adequate factual basis. A guilty plea that lacks an adequate factual basis is not a valid plea.13 A similar inquiry also applies to ensure that a defendant understands the basis for his plea, even when the plea is "no contest." 14
The court is not required to conduct a trial or follow the rules of evidence when it determines the basis for a guilty plea.15 But the court's inquiry should be sufficiently definite to establish that there is a factual basis for the plea:
The court should satisfy itself, by inquiry of the defendant or the attorney for the «government, or by examining the presen-tence report, or otherwise, that the conduct which the defendant admits constitutes the offense charged in the indictment or information or an offense included therein to which the defendant has pleaded guilty_ [16]
This inquiry may be achieved by statements and stipulations of counsel, including references to the grand jury transcript, complaint affidavit, or police report.17
In the present case, the superior court did not determine the basis for Ulak's guilty plea before the judgment was entered. This omission prevented the court from making an accurate determination about whether the acts that Ulak's grandchildren described were the conduct underlying Ulak's convietion. On remand, the superior court must determine the factual basis for Ulak's plea using the methods described above.
The superior court also erred when it failed to determine whether the assertions to which Ulak objected had been proven. Assertions that are included in the factual basis for the plea need no further proof; the defendant's plea proves those assertions.18 But other hearsay assertions that the defendant has denied under oath must be deleted, unless the State submits evidence showing that *1258those assertions are true.19
It is not sufficient for the court to merely note the disputed assertions, or attach the defendant's version of the events to the pre-sentence report. The court must delete the unproven assertions from the presentence report by marking them out so that they cannot be used for improper reference in the future. The court's corrected copy must be labeled the "approved version" of the presen-tence report, and delivered to the Department of Corrections within seven days after the sentencing hearing.20
Judge Coats's dissenting opinion suggests that it is now unfair for the sentencing judge to determine the factual basis for Ulak's plea. Judge Coats would apparently require the judge to delete the hearsay statements from the presentence report even if the deletion would leave a sentencing record without any description of the cireumstances of Ulak's offense. But the circumstances of Ulak's offense are part of the statutory factors the sentencing judge is required to consider.21 Thus Ulak has no right to have the facts that underlie her guilty plea and the aggravating factors she admitted stricken from the pre-sentence report. Even if Ulak now denies these facts, they have been established, for purposes of the presentence report and the sentencing proceeding, based on Ulak's decision to enter a guilty plea.22
We realize that Rule 11(f) only requires a judge to ensure that there is a reasonable basis for a guilty plea before issuing the judgment. We note, however, that the trial court's failure to explicitly determine the factual basis for Ulak's guilty plea has resulted in a great deal of litigation on this issue. If trial judges determine the factual basis for a guilty or no contest plea at the time the plea is entered and accepted, this will avoid unnecessary disputes.
We therefore REMAND this case to the superior court for further proceedings. The court shall explicitly determine the factual basis for Ulak's guilty plea and the aggravating factors she admitted. The court shall then focus on the assertions in the presen-tence report that Ulak has disputed in her testimonial denials. The court may allow the State an opportunity to present testimony to corroborate the grandchildren's statements. The disputed assertions that are not proven either by Ulak's plea, admission, or other evidence shall be deleted from the report. We do not retain jurisdiction of this matter.
MANNHEIMER, Judge, concurring.
COATS, Chief Judge, concurring in part and dissenting in part.
. AS 11.41.220(a)(1)(C)@).
. AS 12.55.155(c)(2) & (c)(5).
. Alaska R.Crim. P. 32.1(d)(5), (f)(5).
. Nukapigak v. State, 562 P.2d 697, 701 (Alaska 1977).
. Hamilton v. State, 771 P.2d 1358, 1362-63 (Alaska App.1989).
. Alaska R.Crim. P. 32.1(f)(5).
. Ashenfelter v. State, 988 P.2d 120, 123 (Alaska App.1999); Scott v. State, 928 P.2d 1234, 1238 (Alaska App.1996).
. Evans v. State, 23 P.3d 650, 652 (Alaska App. 2001).
. Alaska R.Crim. P. 32.1(c)(1).
. AS 12.55.155(f)(1); Alaska R.Crim. P. 32.1(f)(2).
. Malutin v. State, 198 P.3d 1177, 1184 (Alaska App.2009).
. Id. at 1185.
. See Swensen v. Anchorage, 616 P.2d 874, 880-81 (Alaska 1980); Else v. State, 555 P.2d 1210, 1215 n. 15 (Alaska 1976); see generally 1A Charles Alan Wright & Andrew D. Leipold, Federal Practice and Procedure, § 179 (4th ed.2008).
. See Lamb v. Anderson, 147 P.3d 736, 742 n. 47 (Alaska 2006); Johnson v. State, 739 P.2d 781, 784 n. 3 (Alaska App.1987).
. See People v. Watts, 67 Cal.App.3d 173, 136 Cal.Rptr. 496, 500 (1977).
. Advisory Committee's Note to the Amendment to Rule 11, Federal Rules of Criminal Procedure, 39 FRD. 69, 172 (1966); see Jones v. State, 215 P.3d 1091, 1095 (Alaska App.2009) (noting that Alaska Criminal Rule 11(f) was prompted by the amendment of the federal rule).
. See People v. Holmes, 32 Cal.4th 432, 9 Cal.Rptr.3d 678, 84 P.3d 366, 372 (2004); Watts, 136 Cal.Rptr. at 500.
. Evans, 23 P.3d at 652.
. Id.
. Alaska R.Crim. P. 32.1(f)(5).
. AS 12.55.005(1) & (4).
. See Evans, 23 P.3d at 652; Ashenfelter, 988 P.2d at 123.